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arXiv · 2301.13610

Non-Singular Bouncing Model in Energy Momentum Squared Gravity

Z. Yousaf·M. Z. Bhatti·H. Aman·P. K. Sahoo
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Abstract

This work is concerned to study the bouncing nature of the universe for an isotropic configuration of fluid $\mathcal{T}_{αβ}$ and Friedmann-Lemaître-Robertson-Walker metric scheme. This work is carried out under the novel $f(\mathcal{G},\mathcal{T}_{αβ} \mathcal{T}^{αβ})$ gravitation by assuming a specific model i.e, $f(\mathcal{G},\mathcal{T}^2)=\mathcal{G}+α\mathcal{G}^2+2λ\mathcal{T}^2$ with $α$ and $λ$ are constants, serving as free parameters. {The terms $\mathcal{G}$ and $\mathcal{T}^2$ served as an Gauss-Bonnet invariant and square of the energy-momentum trace term as an inclusion in the gravitational action respectively, and is proportional to $\mathcal{T}^2=\mathcal{T}_{αβ} \mathcal{T}^{αβ}$.} A specific functional form of the Hubble parameter is taken to provide the evolution of cosmographic parameters. A well known equation of state parameter, $ω(t)=-\frac{k \log (t+ε)}{t}-1$ is used to represent the dynamical behavior of energy density, matter pressure and energy conditions. A detailed graphical analysis is also provided to review the bounce. Furthermore, all free parameters are set in a way, to make the supposed Hubble parameter act as the bouncing solution and ensure the viability of energy conditions. Conclusively, all necessary conditions for a bouncing model are checked.

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Z. Yousaf, M. Z. Bhatti, H. Aman, P. K. Sahoo. 2023-01-30. Non-Singular Bouncing Model in Energy Momentum Squared Gravity. https://doi.org/10.1088/1402-4896%2Facb6c3

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