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arXiv · 2409.14024

Constrained transit cosmological models in $f(R,L_{m},T)$-gravity

Dinesh Chandra Maurya
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Abstract

In the present paper, we investigate constrained transit cosmological models in the most recent proposed modified gravity theory, $f(R,L_{m},T)$-gravity. We obtain the modified field equations for a flat homogeneous and isotropic Friedmann-Lema\^ıtre-Robertson-Walker (FLRW) spacetime metric. We constrain the equation of continuity by imposing the equation of state for the perfect fluid source $p=-\frac{1}{3}ρ+p_{0}$ so that we get energy conservation equation as $\dotρ+3H(ρ+p)=0$, (because generally, energy conservation law is not satisfied in $f(R,L_{m},T)$-gravity). Using this constraint, we establish a relation between the energy density parameters $Ω_{m0}$, $Ω_{r0}$, and $Ω_{f0}$ and the Hubble function. After that, we made observational constraints on $H(z)$ to obtain the best-fit present values of $Ω_{m0}$, $Ω_{r0}$, and $H_{0}$. Then, we use these best-fit values of energy parameters to investigate cosmological parameters such as the deceleration parameter, the effective equation of state $ω_{eff}$, and the energy density parameters $Ω_{m}$, $Ω_{r}$, and $Ω_{f}$ to learn more about the components and history of the expanding universe. We found an effective EoS parameter in the range $-1\le ω_{eff}\le\frac{1}{3}$ with a deceleration-acceleration transition redshift value of $z_{t}=0.6377, 0.6424$ along two datasets cosmic chronometer (CC) and Pantheon SNIa, respectively.

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Dinesh Chandra Maurya. 2024-12-19. Constrained transit cosmological models in $f(R,L_{m},T)$-gravity. https://doi.org/10.1142/s0219887825500288

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