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arXiv · 2303.06961

Observational constraints on non-minimally coupled curvature-matter models of gravity from the analysis of Pantheon data

Abstract

We considered non-minimally coupled curvature-matter models of gravity in a FRW universe filled with perfect fluid and investigated its cosmological implications in the light of Pantheon compilation of 1048 Supernovae Ia data points along with 54 data points from Observed Hubble Data. The non-minimal curvature-matter coupling has been introduced by adding a term $\int \left[\lambda R^n \mathcal{L}_m\right] \sqrt{-g}d^4x$ to the usual action for Einstein gravity involving the Einstein Hilbert action and minimally coupled matter action. We investigate the observational constraints on the non-minimal models by choosing two different kinds of parametrization of fluid-pressure profiles using a dimensionless parameter $k$. The interplay of the three parameters $\lambda,n,k$ plays a pivotal role in testing the consistency of non-minimally coupled fluid-curvature scenarios with the observed data. We found there exist large domains in the ($\lambda,n,k$)-parameter space for which models with non-minimal curvature-matter mixing stand as viable cosmological models reproducing the observed features of late-time cosmic evolution. We also commented on the possibility of `gravitationally induced particle creation' in the context of SNe Ia data.

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Biswajit Jana, Anirban Chatterjee, Kumar Ravi, Abhijit Bandyopadhyay. 2023-03-13. Observational constraints on non-minimally coupled curvature-matter models of gravity from the analysis of Pantheon data. https://arxiv.org/abs/2303.06961

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