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arXiv · 2212.10928

Friedmann equations and cosmic bounce in a modified cosmological scenario

Ana Alonso-Serrano·Marek Liška·Antonio Vicente-Becerril
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Abstract

In this work we present a derivation of modified Raychaudhuri and Friedmann equations from a phenomenological model of quantum gravity based on the thermodynamics of spacetime. Starting from general gravitational equations of motion which encode low-energy quantum gravity effects, we found its particular solution for homogenous and isotropic universes with standard matter content, obtaining a modified Raychaudhuri equation. Then, we imposed local energy conservation and used a perturbative treatment to derive a modified Friedmann equation. The modified evolution in the early universe we obtained suggests a replacement of the Big Bang singularity by a regular bounce. Lastly, we also briefly discuss the range of validity of the perturbative approach and its results.

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Ana Alonso-Serrano, Marek Liška, Antonio Vicente-Becerril. 2022-12-21. Friedmann equations and cosmic bounce in a modified cosmological scenario. https://doi.org/10.1016/j.physletb.2023.137827

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