Constraint on the equation of state parameter ($\omega$) in non-minimally coupled $f(Q)$ gravity

TL;DR

This paper constrains the equation of state parameter in non-minimally coupled $f(Q)$ gravity using observational data, revealing a quintessence-like behavior that deviates from the standard $ ext{ extLambda}$CDM model.

Contribution

It provides new observational constraints on the $f(Q)$ gravity model's parameters, specifically on the equation of state parameter $ extomega$, using diverse cosmological data sets.

Findings

The equation of state parameter $ extomega$ is approximately -0.85 with Hubble data.

The $ extomega$ value is approximately -0.80 with Pantheon supernova data.

The $f(Q)$ model exhibits quintessence behavior, deviating from $ extLambda$CDM.

Abstract

We study observational constraints on the modified symmetric teleparallel gravity, the non-metricity $f(Q)$ gravity, which reproduces background expansion of the universe. For this purpose, we use Hubble measurements, Baryonic Acoustic Oscillations (BAO), 1048 Pantheon supernovae type Ia data sample which integrate SuperNova Legacy Survey (SNLS), Sloan Digital Sky Survey (SDSS), Hubble Space Telescope (HST) survey, Panoramic Survey Telescope and Rapid Response System (Pan-STARRS1). We confront our cosmological model against observational samples to set constraints on the parameters using Markov Chain Monte Carlo (MCMC) methods. We find the equation of state parameter $\omega=-0.853^{+0.015}_{-0.020}$ and $\omega= -0.796^{+0.049}_{-0.074}$ for Hubble and Pantheon samples, respectively. As a result, the $f(Q)$ model shows the quintessence behavior and deviates from $\Lambda$CDM.