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arXiv · 2406.04444

Observational constraints on thawing quintessence scalar field model

Fereshteh Felegary·Kazuharu Bamba
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Abstract

Thawing quintessence scalar field models with the various potential forms to explain the late-time cosmic acceleration are compared to the {\Lambda}CDM model in detail by analyzing cosmological parameters with a set of observational data including H(z), BAO, CMB, SNIa, BBN, and f(z){\sigma}8 at the background and the perturbation levels. At low redshifts for the thawing quintessence scalar field models, the growth rate of the cosmic structure is significant. By utilizing a standard Markov Chain Monte Carlo (MCMC) procedure based on the recent expansion and the growth observational data with the statistical values of the Akaike and the Bayesian information criteria, we discuss the consistency of the thawing quintessence scalar field models with the set of different potentials with the observational data. The main consequence of this work is that despite the various considered potential forms that are very popular in the literature, we should be looking for consistent potential forms with observational data. Keywords: Thawing Dark Energy, Large Scale Structure, Markov Chain Monte Carlo Method, Observational Constraints, Matter Perturbations.

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Fereshteh Felegary, Kazuharu Bamba. 2024-06-06. Observational constraints on thawing quintessence scalar field model. https://doi.org/10.1016/j.dark.2024.101435

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