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arXiv · 1909.11106

Trans-Planckian Censorship and Inflationary Cosmology

Alek Bedroya·Robert Brandenberger·Marilena Loverde·Cumrun Vafa
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Abstract

We study the implications of the recently proposed Trans-Planckian Censorship Conjecture (TCC) for early universe cosmology and in particular inflationary cosmology. The TCC leads to the conclusion that if we want inflationary cosmology to provide a successful scenario for cosmological structure formation, the energy scale of inflation has to be lower than $10^9$ GeV. Demanding the correct amplitude of the cosmological perturbations then forces the generalized slow-roll parameter $\epsilon$ of the model to be very small ($<10^{-31}$). This leads to the prediction of a negligible amplitude of primordial gravitational waves. For slow-roll inflation models, it also leads to severe fine tuning of initial conditions.

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Alek Bedroya, Robert Brandenberger, Marilena Loverde, Cumrun Vafa. 2019-09-24. Trans-Planckian Censorship and Inflationary Cosmology. https://doi.org/10.1103/physrevd.101.103502

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