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arXiv · hep-ph/9706274

Renormalization of nonequilibrium dynamics in FRW cosmology

Jurgen Baacke·Katrin Heitmann·Carsten Patzold
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Abstract

We derive the renormalized nonequilibrium equations of motion for a scalar field and its quantum back reaction in a conformally flat Friedmann-Robertson-Walker universe. We use a fully covariant formalism proposed by us recently for handling numerically and analytically nonequilibrium dynamics in one-loop approximation. The system is assumed to be in a conformal vacuum state initially. We use dimensional regularization; we find that the counter terms can be chosen independent of the initial conditions though the divergent leading order graphs do depend on them.

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Jurgen Baacke, Katrin Heitmann, Carsten Patzold. 1997-07-28. Renormalization of nonequilibrium dynamics in FRW cosmology. https://doi.org/10.1103/physrevd.56.6556

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