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arXiv · 2009.12653

Entanglement entropy of cosmological perturbations for S-brane Ekpyrosis

Suddhasattwa Brahma·Robert Brandenberger·Ziwei Wang
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Abstract

We calculate the entanglement entropy of scalar perturbations due to gravitational non-linearities present in any model of canonically-coupled, single-field ekpyrosis. Specifically, we focus on a recent model of improved ekpyrosis which is able to generate a scale-invariant power spectrum of curvature perturbations and gravitational waves as well as have a non-singular bounce due to an S-brane at the end of ekpyrotic contraction. By requiring that the entanglement entropy remians subdominant to the thermal entropy produced during reheating, we get an upper bound on the energy scale of the bounce.

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Suddhasattwa Brahma, Robert Brandenberger, Ziwei Wang. 2020-09-26. Entanglement entropy of cosmological perturbations for S-brane Ekpyrosis. https://doi.org/10.1088/1475-7516/2021/03/094

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