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arXiv · 2009.14630

Observational Constraint in $f(R,T)$ gravity from the cosmic chronometers and some standard distance measurement parameters

Prabir Rudra·Kinsuk Giri
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Abstract

In this work we perform an observational data analysis on the $f(R,T)$ gravity with the aim of constraining the parameter space of the model. Five different models are considered and the 30 point $z-H(z)$ cosmic chronometer data is used in our analysis. The $\chi^2$ statistic is formulated as a difference between the theoretical and the observed values of $H(z)$ for different values of redshift $z$. Efforts have been made to minimize the statistic in order to get the best fit values for the free parameters models. We have also used some standard distance measurement parameters like BAO and CMB peaks along with the data for achieving better constraints on the parameter space. We have used the publicly available \textit{CosmoMC} code for obtaining the bounds for the free parameters of the models in different confidence intervals like $68\%$, $95\%$, $99\%$. 1D distributions and 2D joint confidence contours for various confidence levels mentioned above are generated for the free parameters using the \textit{CosmoMC} code. Finally our models have been compared with the standard $\Lambda CDM$ model by some statistical techniques using the observational data and the support for the models from the data is probed.

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Prabir Rudra, Kinsuk Giri. 2020-09-28. Observational Constraint in $f(R,T)$ gravity from the cosmic chronometers and some standard distance measurement parameters. https://doi.org/10.1016/j.nuclphysb.2021.115428

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