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arXiv · 1711.08473

Gravitational wave signals and cosmological consequences of gravitational reheating

Michał Artymowski·Olga Czerwińska·Zygmunt Lalak·Marek Lewicki
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Abstract

Reheating after inflation can proceed even if the inflaton couples to Standard Model (SM) particles only gravitationally. However, particle production during the transition between de-Sitter expansion and a decelerating Universe is rather inefficient and the necessity to recover the visible Universe leads to a non-standard cosmological evolution initially dominated by remnants of the inflaton field. We remain agnostic to the specific dynamics of the inflaton field and discuss a generic scenario in which its remnants behave as a perfect fluid with a general barotropic parameter $w$. Using CMB and BBN constraints we derive the allowed range of inflationary scales. We also show that this scenario results in a characteristic primordial Gravitational Wave (GW) spectrum which gives hope for observation in upcoming runs of LIGO as well as in other planned experiments.

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Michał Artymowski, Olga Czerwińska, Zygmunt Lalak, Marek Lewicki. 2017-11-22. Gravitational wave signals and cosmological consequences of gravitational reheating. https://doi.org/10.1088/1475-7516%2F2018%2F04%2F046

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