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arXiv · 0712.2991

Gravitational Waves From the End of Inflation: Computational Strategies

Richard Easther·John T. Giblin Jr·Eugene A. Lim
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Abstract

Parametric resonance or preheating is a plausible mechanism for bringing about the transition between the inflationary phase and a hot, radiation dominated universe. This epoch results in the rapid production of heavy particles far from thermal equilibrium and could source a significant stochastic background of gravitational radiation. Here, we present a numerical algorithm for computing the contemporary power spectrum of gravity waves generated in this post-inflationary phase transition for a large class of scalar-field driven inflationary models. We explicitly calculate this spectrum for both quartic and quadratic models of chaotic inflation, and low-scale hybrid models. In particular, we consider hybrid models with an ``inverted'' potential. These models have a very short and intense period of resonance which is qualitatively different from previous examples studied in this context, but we find that they lead to a similar spectrum of gravitational radiation.

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Richard Easther, John T. Giblin Jr, Eugene A. Lim. 2007-12-18. Gravitational Waves From the End of Inflation: Computational Strategies. https://doi.org/10.1103/physrevd.77.103519

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