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On Metric Preheating

Karsten Jedamzik·Guenter Sigl
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Abstract

We consider the generation of super-horizon metric fluctuations during an epoch of preheating in the presence of a scalar field χquadratically coupled to the inflaton. We find that the requirement of efficient broad resonance is concomitant with a severe damping of super-horizon δχquantum fluctuations during inflation. Employing perturbation theory with backreaction included as spatial averages to second order in the scalar fields and in the metric, we argue that the usual inflationary prediction for metric perturbations on scales relevant for structure formation is not strongly modified.

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Karsten Jedamzik, Guenter Sigl. 1999-06-22. On Metric Preheating. https://doi.org/10.1103/physrevd.61.023519

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