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arXiv · 1702.04916

Constraints on a generalized deceleration parameter from cosmic chronometers

Abdulla Al Mamon
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Abstract

In this paper, we have proposed a generalized parametrization for the deceleration parameter $q$ in order to study the evolutionary history of the universe. We have shown that the proposed model can reproduce three well known $q$-parametrized models for some specific values of the model parameter $α$. We have used the latest compilation of the Hubble parameter measurements obtained from the cosmic chronometer (CC) method (in combination with the local value of the Hubble constant $H_{0}$) and the Type Ia supernova (SNIa) data to place constraints on the parameters of the model for different values of $α$. We have found that the resulting constraints on the deceleration parameter and the dark energy equation of state support the $Λ$CDM model within $1σ$ confidence level at the present epoch.

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Abdulla Al Mamon. 2018-03-16. Constraints on a generalized deceleration parameter from cosmic chronometers. https://doi.org/10.1142/s0217732318500566

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