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arXiv · 2208.04723

A new parametrization of Hubble parameter in $f(Q)$ gravity

M. Koussour·S. K. J. Pacif·M. Bennai·P. K. Sahoo
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Abstract

In this paper, we examine the accelerated expansion of the Universe at late-time in the framework of $f\left( Q\right) $ gravity theory in which the non-metricity scalar $Q$ describes the gravitational interaction. To this, we propose a new parametrization of the Hubble parameter using a model-independent way and apply it to the Friedmann equations in the FLRW Universe. Then we estimate the best fit values of the model parameters by using the combined datasets of updated $H(z)$ consisting of $57$ points, the Pantheon consisting of $1048$ points, and BAO datasets consisting of six points with the Markov Chain Monte Carlo (MCMC) method. The evolution of deceleration parameter indicates a transition from the deceleration to the acceleration phase of the Universe. In addition, we investigate the behavior of statefinder analysis and Om diagnostic parameter, Further, to discuss other cosmological parameters, we consider a $f\left( Q\right) $\ model, specifically, $f\left( Q\right) =Q+mQ^{n}$, where $m$ and $n$ are free parameters. Finally, we find that the model supports the present accelerating Universe, and the EoS parameter behaves like the quintessence model.

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M. Koussour, S. K. J. Pacif, M. Bennai, P. K. Sahoo. 2022-08-08. A new parametrization of Hubble parameter in $f(Q)$ gravity. https://doi.org/10.1002/prop.202200172

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