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When can preheating affect the CMB?

Shinji Tsujikawa·Bruce A. Bassett
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Abstract

We discuss the principles governing the selection of inflationary models for which preheating can affect the CMB. This is a (fairly small) subset of those models which have non-negligible entropy/isocurvature perturbations on large scales during inflation. We study new models which belong to this class - two-field inflation with negative nonminimal coupling and hybrid/double/supernatural inflation models where the tachyonic growth of entropy perturbations can lead to the variation of the curvature perturbation, ${\cal R}$, on super-Hubble scales. Finally we present evidence against recent claims for the variation of ${\cal R}$ in the absence of substantial super-Hubble entropy perturbations.

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Shinji Tsujikawa, Bruce A. Bassett. 2002-04-02. When can preheating affect the CMB?. https://doi.org/10.1016/s0370-2693(02)01813-0

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