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arXiv · 1203.4943

Stochastic Background of Gravitational Waves from Fermions

Kari Enqvist·Daniel G. Figueroa·Tuukka Meriniemi
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Abstract

Preheating and other particle production phenomena in the early Universe can give rise to high- energy out-of-equilibrium fermions with an anisotropic stress. We develop a formalism to calculate the spectrum of gravitational waves due to fermions, and apply it to a variety of scenarios after inflation. We pay particular attention to regularization issues. We show that fermion production sources a stochastic background of gravitational waves with a significant amplitude, but we find that typical frequencies of this new background are not within the presently accessible direct detec- tion range. However, small-coupling scenarios might still produce a signal observable by planned detectors, and thus open a new window into the physics of the very early Universe.

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Kari Enqvist, Daniel G. Figueroa, Tuukka Meriniemi. 2012-03-22. Stochastic Background of Gravitational Waves from Fermions. https://doi.org/10.1103/physrevd.86.061301

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