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arXiv · 2305.14400

The Reconstruction of Constant Jerk Parameter with $f(R,T)$ Gravity in Bianchi-I spacetime

Anirudh Pradhan·Gopikant Goswami·Syamala Krishnannair
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Abstract

We have developed a Bianchi I cosmological model of the universe in $f(R,T)$ gravity theory which fit good with the present day scenario of accelerating universe. The model displays transition from deceleration in the past to the acceleration at the present. As in the $\Lambda$CDM model, we have defined the three energy parameters $\Omega_m$, $\Omega_{\mu}$ and $\Omega_{\sigma}$ such that $\Omega_m$ + $\Omega_{\mu}$ + $\Omega_{\sigma}$ = 1. The parameter $\Omega_m$ is the matter energy density (baryons + dark matter), $\Omega_{\mu}$ is the energy density associated with the Ricci scalar $R$ and the trace $T$ of the energy momentum tensor and $\Omega_{\sigma}$ is the energy density associated with the anisotropy of the universe. We shall call $\Omega_{\mu}$ dominant over the other two due to its higher value. We find that the $\Omega_{\mu}$ and the other two in the ratio 3:1. 46 Hubble OHD data set is used to estimate present values of Hubble $H_0$, deceleration $q_0$ and jerk $j$ parameters. 1$\sigma$, 2$\sigma$ and 3$\sigma$ contour region plots for the estimated values of parameters are presented. 580 SNIa supernova distance modulus data set and 66 pantheon SNIa data which include high red shift data in the range $0\leq z\leq 2.36$ have been used to draw error bar plots and likelihood probability curves for distance modulus and apparent magnitude of SNIa supernova's. We have calculated the pressures and densities associated with the two matter densities, viz., $p_{\mu}$, $\rho_{\mu}$, $p_m$ and $\rho_m$, respectively. The present age of the universe as per our model is also evaluated and it is found at par with the present observed values.

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Anirudh Pradhan, Gopikant Goswami, Syamala Krishnannair. 2023-05-23. The Reconstruction of Constant Jerk Parameter with $f(R,T)$ Gravity in Bianchi-I spacetime. https://doi.org/10.1140/epjp%2Fs13360-023-04057-3

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