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arXiv · 2403.19458

Evaluation of Transit cosmological model in $f(R,T^{\phi})$ theory of gravity

Abstract

We have explored a transitioning cosmic model, depicting late-time accelerated expansion in $f(R,T^{\phi})$ theory of gravity for an isotropic and homogeneous universe, where the trace of energy-momentum tensor $T^{\phi}$ is the function of the self-interacting scalar field $\phi$. We have proposed an explicit solution to the derived model by utilizing a scale factor of the hybrid form $a(t) = t^{\alpha} e^{\beta t}$, where $\alpha$ and $\beta$ are constants. To evaluate the best-fit values of free parameters of the suggested model, the statistical analysis based on the Markov Chain Monte Carlo (MCMC) method has been employed on 57 OHD points. We have described the dynamical features of the model like energy density, cosmic pressure, and equation of state parameter in the context of scalar field $\phi$. We have also described the potential and behavior of the scalar field for quintessence and phantom scenarios. The deceleration parameter depicts a transitioning universe with signature flipping at $z_t = 0.82$ with the present value of deceleration parameter $q_0=-0.41$. The violation of SEC for the derived model indicates the cosmic expansion at a faster rate. We have used statefinders to diagnose the model. The findings for our theoretical model indicate that the derived model agrees with observed findings within a particular range of limitations.

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BibTeXRIS

Bhojraj Singh Jayas, Vinod Kumar Bhardwaj. 2024-03-28. Evaluation of Transit cosmological model in $f(R,T^{\phi})$ theory of gravity. https://arxiv.org/abs/2403.19458

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