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Time evolution of observables out of thermal equilibrium

Herbert Nachbagauer
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Abstract

We propose a new approximation-technique to deal with the exact macroscopic integro-differential evolution equations of statistical systems which self-consistently accounts for dissipative effects. Concentrating on one and two point equal-time correlators, we develop the self-consistent method and apply it to a scalar field theory with quartic self-interaction. We derive the effective equations of motion and the corresponding macroscopic effective Hamiltonian. Non-locality in time appears in a natural way necessary to account for entropy generating processes.

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Herbert Nachbagauer. 1998-11-26. Time evolution of observables out of thermal equilibrium. https://arxiv.org/abs/hep-ph/9809267

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