English

Constraining Generalized Chaplygin Gas in Non-Minimally Coupled $f(Q)$ Cosmology using Quasars and $H(z)$ Data

General Relativity and Quantum Cosmology 2022-12-02 v1

Abstract

In the current framework of Einstein's equations in general relativity (GR), gravity is described by the spacetime curvature. However, there are other descriptions where the origin of gravity can be understood through torsion and non-metricity QQ. In this work, we discuss a modified theory of gravity namely f(Q)f(Q) gravity, which considers a non-linear extension of QQ. In particular, we study the case where it is non-minimally coupled to matter. Motivated by the recent success of Chaplygin gas models in the explanation of dark energy, we assume a pressureless baryonic matter and a generalized Chaplygin gas as the background fluid. We constrain the proposed model using two different datasets: one for Hubble measurements and the other for quasars (which we calibrated) with Markov-Chain Monte Carlo (MCMC) methods. We employ kinematic tools such as deceleration and jerk parameters to determine deviations of the proposed model from Λ\LambdaCDM. We establish that the transition redshift zTz_T in the deceleration parameter qq is 0.6070.607 and 0.2040.204 with the two datasets respectively, therefore describing the universe's acceleration.

Keywords

Cite

@article{arxiv.2212.00312,
  title  = {Constraining Generalized Chaplygin Gas in Non-Minimally Coupled $f(Q)$ Cosmology using Quasars and $H(z)$ Data},
  author = {Nakul Aggarwal and Ali Pourmand and Fatimah Shojai and Harish Parthasarathy},
  journal= {arXiv preprint arXiv:2212.00312},
  year   = {2022}
}

Comments

17 pages, 5 figures