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arXiv · 2104.11296

Constraints on Tsallis Cosmology from Big Bang Nucleosynthesis and Dark Matter Freeze-out

Anish Ghoshal·Gaetano Lambiase
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Abstract

We consider Tsallis cosmology as an approach to thermodynamic gravity and derive the bound on the Tsallis parameter to be $\beta<2$ by using the constraints derived from the formation of the primordial light elements, Helium, Deuterium and Litium, from the observational data from Big Bang Nucleosynthesis (BBN) which allows only a very tiny deviation from General Relativity (GR). Next we consider thermal dark matter (DM) freeze-out mechanism in Tsallis cosmological era and derive bounds on the Tsallis parameter from the observed DM relic abundance to be $1-\beta < 10^{-5}$.

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Anish Ghoshal, Gaetano Lambiase. 2021-04-22. Constraints on Tsallis Cosmology from Big Bang Nucleosynthesis and Dark Matter Freeze-out. https://arxiv.org/abs/2104.11296

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