Boundary Conditions and Correlations in Path Integrals for Quantum Field Theory of Thermal and Non-Equilibrium States

P. A. Henning; R. Fauser

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arXiv · hep-ph/9605372

Boundary Conditions and Correlations in Path Integrals for Quantum Field Theory of Thermal and Non-Equilibrium States

P. A. Henning·R. Fauser

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Abstract

For thermal equilibrium systems it is shown, how the Kubo-Martin-Schwinger boundary condition may be used to factorize the generating functional of Green functions at least on the level of the full two-point function. Genuine non-equilibrium system exhibit correlations that one may also incorporate in the path integral. One one hand this provides a natural tool for a perturbative expansion including these correlations. On the other hand it allows to prove that in general non-equilibrium systems the generating functional does not factorize.

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P. A. Henning, R. Fauser. 1996-05-22. Boundary Conditions and Correlations in Path Integrals for Quantum Field Theory of Thermal and Non-Equilibrium States. https://arxiv.org/abs/hep-ph/9605372

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