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arXiv · 1710.08913

Effect of reheating on predictions following multiple-field inflation

Selim C. Hotinli·Jonathan Frazer·Andrew H. Jaffe·Joel Meyers·Layne C. Price·Ewan R. M. Tarrant
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Abstract

We study the sensitivity of cosmological observables to the reheating phase following inflation driven by many scalar fields. We describe a method which allows semi-analytic treatment of the impact of perturbative reheating on cosmological perturbations using the sudden decay approximation. Focusing on $\mathcal{N}$-quadratic inflation, we show how the scalar spectral index and tensor-to-scalar ratio are affected by the rates at which the scalar fields decay into radiation. We find that for certain choices of decay rates, reheating following multiple-field inflation can have a significant impact on the prediction of cosmological observables.

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Selim C. Hotinli, Jonathan Frazer, Andrew H. Jaffe, Joel Meyers, Layne C. Price, Ewan R. M. Tarrant. 2017-10-24. Effect of reheating on predictions following multiple-field inflation. https://doi.org/10.1103/physrevd.97.023511

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