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arXiv · 2307.10966

Cosmological evolution from modified Bekenstein entropy law

Marco de Cesare·Giulia Gubitosi
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Abstract

We study the dynamics of the homogeneous and isotropic cosmological background in the recently proposed ``quantum phenomenological gravitational dynamics'', characterised by logarithmic corrections to the Bekenstein entropy. We show that the model admits a family of solutions that are self-accelerating both at early and late times: they approach de Sitter in the future and admit a past attractor corresponding to an inflationary acceleration era. On the other hand, there are no solutions corresponding to a primordial bounce. We also show that asking scalar perturbations to be unaffected by instabilities on observable scales puts stringent constraints on the deviations from general relativity encoded by the model.

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Marco de Cesare, Giulia Gubitosi. 2023-07-20. Cosmological evolution from modified Bekenstein entropy law. https://arxiv.org/abs/2307.10966

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