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arXiv · 2210.09307

Constraining Anisotropic Cosmological Model in $f(\mathcal{R},\mathscr{L}_m)$ Gravity

N. S. Kavya·V. Venkatesha·Sanjay Mandal·P. K. Sahoo
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Abstract

The observational evidence regarding the present cosmological aspects tells us about the presence of very little anisotropy in the universe on a large scale. Here, in this paper, we attempt to study locally rotationally symmetric (LRS) homogeneous Bianchi-I spacetime with the isotropic matter distribution. This is done within the framework of $f(\mathcal{R},\mathscr{L}_m)$ gravity. Particularly, we consider a non-linear $f(\mathcal{R},\mathscr{L}_m)$ model, $f(\mathcal{R},\mathscr{L}_m)=\dfrac{1}{2}\mathcal{R}+\mathscr{L}_m^{\,{\alpha}}$. Furthermore, $\omega$, the equation of state parameter, which is vital stuff in determining the present phase of the universe is constrained. To constrain the model parameters and the equation of state parameter, we use 57 Hubble data points and 1048 Pantheon supernovae type Ia data sample. And, for our statistical analysis, we use Markoc Chain Monte Carlo (MCMC) simulation. Moreover, with the help of obtained values of parameters, we measure the anisotropy parameter for our model.

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N. S. Kavya, V. Venkatesha, Sanjay Mandal, P. K. Sahoo. 2022-10-17. Constraining Anisotropic Cosmological Model in $f(\mathcal{R},\mathscr{L}_m)$ Gravity. https://doi.org/10.1016/j.dark.2022.101126

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