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arXiv · 2402.16275

Baryon asymmetry constraints on Extended Symmetric Teleparallel Gravity

Abstract

In this paper, we have explored the observed matter-antimatter asymmetry in the Universe to constrain the model parameters in extended symmetric teleparallel gravity (STG) or $f(Q,T)$ gravity, where $Q$ be the nonmetricity and $T$ be the trace of energy momentum tensor. We have considered two functional forms of $f(Q,T)$ to find the baryon asymmetry to entropy ratio calculated at a decoupling temperature. Two different data sets namely Hubble data set and the Hubble+BAO+Pantheon data sets are used to constrain the scale factor and the constrained model is used to obtain the baryon asymmetry to entropy ratio. It is observed that, model constrained from the Hubble data set favour a narrow range of the $f(Q,T)$ gravity parameters to reproduce the observed baryon asymmetry.

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BibTeXRIS

S. A. Narawade, S. K. Tripathy, Raghunath Patra, B. Mishra. 2024-02-26. Baryon asymmetry constraints on Extended Symmetric Teleparallel Gravity. https://doi.org/10.1134/s0202289324700026

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