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arXiv · 1603.01118

Backreaction Effects on Nonequilibrium Spectral Function

Sebastian Mendizabal·Juan Cristobal Rojas
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Abstract

We show how to compute the spectral function for a scalar theory in two different scenarios: one which disregards back-reaction i.e. the response of the environment to the external particle, and the other one where back-reaction is considered. The calculation was performed using the Kadanoff-Baym equation through the Keldysh formalism. When back-reaction is neglected, the spectral function is equal to the equilibrium one, which can be represented as a Breit-Wigner distribution. When back-reaction is introduced we observed a damping in the spectral function of the thermal bath. Such behavior modifies the damping rate for particles created within the bath. This certainly implies phenomenological consequences right after the Big-Bang, when the primordial bath was created.

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Sebastian Mendizabal, Juan Cristobal Rojas. 2016-03-03. Backreaction Effects on Nonequilibrium Spectral Function. https://doi.org/10.1142/s0217751x17501263

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