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The role of dissipation in biasing the vacuum selection in quantum field theory at finite temperature

F. Freire·N. D. Antunes·P. Salmi·A. Achucarro
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Abstract

We study the symmetry breaking pattern of an O(4) symmetric model of scalar fields, with both charged and neutral fields, interacting with a photon bath. Nagasawa and Brandenberger argued that in favourable circumstances the vacuum manifold would be reduced from S^3 to S^1. Here it is shown that a selective condensation of the neutral fields, that are not directly coupled to photons, can be achieved in the presence of a minimal ``external'' dissipation, i.e. not related to interactions with a bath. This should be relevant in the early universe or in heavy-ion collisions where dissipation occurs due to expansion.

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F. Freire, N. D. Antunes, P. Salmi, A. Achucarro. 2005-08-26. The role of dissipation in biasing the vacuum selection in quantum field theory at finite temperature. https://doi.org/10.1103/physrevd.72.045017

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