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Nonequilibrium quantum dynamics of phase transitions in an expanding universe

Ian D Lawrie
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Abstract

I summarize the derivation of a set of Feynman rules appropriate for the perturbative description of the nonequilibrium dynamics of the symmetry-breaking phase transition in $λϕ^4$ theory in a Robertson-Walker universe. The approximation scheme I develop provides for a treatment of dissipative effects which are essential to an adequate description of the nonequilibrium state. It also provides for the emergence from an initially symmetric state of a final state exhibiting the properties of spontaneous symmetry breaking without the introduction by hand of any explicit symmetry breaking.

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Ian D Lawrie. 1998-10-15. Nonequilibrium quantum dynamics of phase transitions in an expanding universe. https://arxiv.org/abs/hep-ph/9809469

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