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arXiv · 2302.05070

Dark energy constraint on equation of state parameter in the Weyl type $f(Q,T)$ gravity

Gaurav N. Gadbail·Simran Arora·P. K. Sahoo
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Abstract

The equation of state parameter is a significant method for characterizing dark energy models. We investigate the evolution of the equation of state parameter with redshift using a Bayesian analysis of recent observational datasets (the Cosmic Chronometer data (CC) and Pantheon samples). The Chevallier-Polarski-Linder parametrization of the effective equation of state parameter, $ω_{eff}=ω_0+ω_a \left( \frac{z}{1+z}\right) $, where $ω_0$ and $ω_a$ are free constants, is confined to the Weyl type $f(Q,T)$ gravity, where $Q$ represents the non-metricity and $T$ is the trace of the energy-momentum tensor. We observe the evolution of the deceleration parameter $q$, the density parameter $ρ$, the pressure $p$, and the effective equation of state parameter $ω$. The cosmic data limit for $ω$ does not exclude the possibility of $ω< -1$. It is seen that the parameter $ω$ shows a transition from deceleration to acceleration, as well as a shift from $ω>-1$ to $ω<-1$.

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Gaurav N. Gadbail, Simran Arora, P. K. Sahoo. 2023-02-10. Dark energy constraint on equation of state parameter in the Weyl type $f(Q,T)$ gravity. https://doi.org/10.1016/j.aop.2023.169244

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