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Gravitational waves in preheating

Daniel Tilley·Roy Maartens
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Abstract

We study the evolution of gravitational waves through the preheating era that follows inflation. The oscillating inflaton drives parametric resonant growth of scalar field fluctuations, and although super-Hubble tensor modes are not strongly amplified, they do carry an imprint of preheating. This is clearly seen in the Weyl tensor, which provides a covariant description of gravitational waves.

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Daniel Tilley, Roy Maartens. 2000-02-25. Gravitational waves in preheating. https://doi.org/10.1088/0264-9381%2F17%2F15%2F303

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