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arXiv · 1403.6850

BICEP2 in Corpuscular Description of Inflation

Gia Dvali·Cesar Gomez
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Abstract

A corpuscular quantum description of inflation shows that there is no fundamental problem with trans-Planckian excursions of the inflaton field up to about 100 Planck masses, with the upper bound coming from the corpuscular quantum effects. In this description the r-parameter measures the ratio of occupation numbers of gravitons versus inflatons, which, according to BICEP2, was roughly a half at the time of 60 e-foldings prior to the end of inflation. We stress that in non-Wilsonian UV self-completion of gravity any trans-Planckian mode coupled to inflaton is a black hole. Unlike the Wilsonian case, their integration-out gives an exponentially-suppressed effect and is unable to prevent trans-Planckian excursions of the inflaton field.

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Gia Dvali, Cesar Gomez. 2014-03-26. BICEP2 in Corpuscular Description of Inflation. https://doi.org/10.1134/s106377611503019x

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