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arXiv · hep-th/9310120

Decoherence and Dissipation for a Quantum System Coupled to a Local Environment

Michael R. Gallis
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Abstract

Decoherence and dissipation in quantum systems has been studied extensively in the context of Quantum Brownian Motion. Effective decoherence in coarse grained quantum systems has been a central issue in recent efforts by Zurek and by Hartle and Gell-Mann to address the Quantum Measurement Problem. Although these models can yield very general classical phenomenology, they are incapable of reproducing relevant characteristics expected of a local environment on a quantum system, such as the characteristic dependence of decoherence on environment spatial correlations. I discuss the characteristics of Quantum Brownian Motion in a local environment by examining aspects of first principle calculations and by the construction of phenomenological models. Effective quantum Langevin equations and master equations are presented in a variety of representations. Comparisons are made with standard results such as the Caldeira-Leggett master equation.

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Michael R. Gallis. 1993-10-19. Decoherence and Dissipation for a Quantum System Coupled to a Local Environment. https://arxiv.org/abs/hep-th/9310120

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