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Parametric Amplification of Metric Fluctuations During Reheating in Two Field Models

F. Finelli·R. Brandenberger
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Abstract

We study the parametric amplification of super-Hubble-scale scalar metric fluctuations at the end of inflation in some specific two-field models of inflation, a class of which is motivated by hybrid inflation. We demonstrate that there can indeed be a large growth of fluctuations due to parametric resonance and that this effect is not taken into account by the conventional theory of isocurvature perturbations. Scalar field interactions play a crucial role in this analysis. We discuss the conditions under which there can be nontrivial parametric resonance effects on large scales.

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F. Finelli, R. Brandenberger. 2000-03-17. Parametric Amplification of Metric Fluctuations During Reheating in Two Field Models. https://doi.org/10.1103/physrevd.62.083502

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