Constraints on Power Law and Exponential models in $f(Q)$ Gravity

TL;DR

This study tests two specific f(Q) gravity models against observational data, finding the exponential model statistically outperforms the power-law and standard Lambda CDM models in explaining cosmic acceleration.

Contribution

It provides the first observational constraints on power-law and exponential f(Q) gravity models using comprehensive cosmological data and statistical model comparison techniques.

Findings

Exponential f(Q) model is statistically favored over power-law and Lambda CDM models.

Best-fit parameters are obtained through MCMC analysis of cosmological data.

The models are tested at both background and perturbation levels.

Abstract

In this paper, we observationally test the \( f(Q) \) gravity model at both background and perturbation levels using Pantheon$^+$, Hubble measurements, and Redshift Space Distortion Data. We obtain the best-fit parameters by solving numerically the modified Friedmann equations for two distinct cosmological models of \( f(Q) \) gravity namely the Power law and Exponential models. This involves performing a Markov Chain Monte Carlo analysis for these specific forms of \( f(Q) \). To evaluate the statistical significance of the \( f(Q) \) gravity models, we use the Bayesian and corrected Akaike Information Criteria. Our results indicate that the Exponential model in \( f(Q) \) gravity is statistically favored over both the Power-law model and the \( \Lambda \)CDM model.