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Transport equations including many-particle correlations for an arbitrary quantum system. General formalism

J. Fricke
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Abstract

We present a new method to derive transport equations for quantum many-particle systems. This method uses an equation-of-motion technique and is applicable to systems with bosons and fermions, arbitrary interactions and time-dependent external fields. Using a cluster expansion of the r-particle density matrices the infinite hierarchy of equations of motion for many-particle expectation values is transposed into an equivalent one in terms of correlations. This new hierarchy permits a systematic breaking of the hierarchy at any order. Diagrams are derived for these transport equations. In a second paper the method is tested for exactly soluble electron-phonon models in one dimension.

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BibTeXRIS

J. Fricke. 1996-10-16. Transport equations including many-particle correlations for an arbitrary quantum system. General formalism. https://doi.org/10.1006/aphy.1996.0142

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