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arXiv · 1006.0935

Gravitational Radiation from Preheating with Many Fields

John T. Giblin Jr·Larry R. Price·Xavier Siemens
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Abstract

Parametric resonances provide a mechanism by which particles can be created just after inflation. Thus far, attention has focused on a single or many inflaton fields coupled to a single scalar field. However, generically we expect the inflaton to couple to many other relativistic degrees of freedom present in the early universe. Using simulations in an expanding Friedmann-Lema\^itre-Robertson-Walker spacetime, in this paper we show how preheating is affected by the addition of multiple fields coupled to the inflaton. We focus our attention on gravitational wave production--an important potential observational signature of the preheating stage. We find that preheating and its gravitational wave signature is robust to the coupling of the inflaton to more matter fields.

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John T. Giblin Jr, Larry R. Price, Xavier Siemens. 2010-06-04. Gravitational Radiation from Preheating with Many Fields. https://doi.org/10.1088/1475-7516/2010/08/012

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