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arXiv · 0910.5733

Decoherence in an Interacting Quantum Field Theory: The Vacuum Case

Jurjen F. Koksma·Tomislav Prokopec·Michael G. Schmidt
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Abstract

We apply the decoherence formalism to an interacting scalar field theory. In the spirit of the decoherence literature, we consider a "system field" and an "environment field" that interact via a cubic coupling. We solve for the propagator of the system field, where we include the self-energy corrections due to the interaction with the environment field. In this paper, we consider an environment in the vacuum state (T=0). We show that neglecting inaccessible non-Gaussian correlators increases the entropy of the system as perceived by the observer. Moreover, we consider the effect of a changing mass of the system field in the adiabatic regime, and we find that at late times no additional entropy has been generated.

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Jurjen F. Koksma, Tomislav Prokopec, Michael G. Schmidt. 2009-10-29. Decoherence in an Interacting Quantum Field Theory: The Vacuum Case. https://doi.org/10.1103/physrevd.81.065030

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