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Simulating nonequilibrium quantum fields with stochastic quantization techniques

J. Berges·I. -O. Stamatescu
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Abstract

We present lattice simulations of nonequilibrium quantum fields in Minkowskian space-time. Starting from a non-thermal initial state, the real-time quantum ensemble in 3+1 dimensions is constructed by a stochastic process in an additional (5th) ``Langevin-time''. For the example of a self-interacting scalar field we show how to resolve apparent unstable Langevin dynamics, and compare our quantum results with those obtained in classical field theory. Such a direct simulation method is crucial for our understanding of collision experiments of heavy nuclei or other nonequilibrium phenomena in strongly coupled quantum many-body systems.

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J. Berges, I. -O. Stamatescu. 2005-10-31. Simulating nonequilibrium quantum fields with stochastic quantization techniques. https://doi.org/10.1103/physrevlett.95.202003

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