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arXiv · 2405.04797

Bouncing cosmological models in $f(R,L_m)$ gravity

Lakhan V. Jaybhaye·Raja Solanki·P. K. Sahoo
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Abstract

This article explores matter bounce non-singular cosmology in $f(R,L_m)$ gravity. We consider two non-linear $f(R,L_m)$ functional forms, specifically, $f(R,L_m) = \frac{R}{2} + \lambda R^2 + \alpha L_m$ and $f(R,L_m) = \frac{R}{2} + L_m ^\beta + \gamma$ representing a minimal coupling case. We derive the corresponding Friedmann-like equations for both the assumed models in the FLRW background, and then we present the impact of the model parameters along with the parameter of bouncing scale factor on the equation of state parameter, pressure, and the energy density. In addition, we examine the dynamical behavior of cosmographic parameters such as jerk, lerk, and snap parameters. Further, we find that the violation of the null energy condition along with the strong energy condition depicts the non-singular accelerating behavior, corresponding to both assumed non-linear $f(R,L_m)$ functions. Lastly, we present the behavior of the adiabatic speed of sound to examine the viability of the considered cosmological bouncing scenario.

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Lakhan V. Jaybhaye, Raja Solanki, P. K. Sahoo. 2024-05-08. Bouncing cosmological models in $f(R,L_m)$ gravity. https://doi.org/10.1088/1402-4896%2Fad4838

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