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arXiv · 2304.02652

Model-independent study for a quintessence model of dark energy: Analysis and Observational constraints

Abstract

In this paper, a well-motivated parametrization of the Hubble parameter ($H$% ) is revisited that renders two models of dark energy showing some intriguing features of the late-time accelerating Universe. A general quintessence field is considered as a source of dark energy. We have obtained tighter constraints using recently updated cosmic observational datasets for the considered models. The two models described here show a nice fit to the considered uncorrelated Hubble datasets, Standard candles, Gamma Ray Bursts, Quasars, and uncorrelated Baryonic Acoustic Oscillations datasets. Using the constrained values of the model parameters, we have discussed some features of the late-time accelerating models and obtained the present value of the deceleration parameter ($q_{0}$), the present value of the Hubble parameter ($H_{0}$) and the transition redshift ($z_{t}$) from deceleration to acceleration. The current value of the deceleration parameter for both models is consistent with the Planck 2018 results. The evolution of the geometrical and physical parameters is discussed through graphical representations for both models with some diagnostic analysis. The statistical analysis performed here shows greater results and overall, the outcomes of this investigation are superior to those previously found.

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Amine Bouali, Himanshu Chaudhary, Amritansh Mehrotra, S. K. J. Pacif. 2023-09-15. Model-independent study for a quintessence model of dark energy: Analysis and Observational constraints. https://doi.org/10.1002/prop.202300086

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