Viability of general relativity and modified gravity cosmologies using high-redshift cosmic probes

TL;DR

This study evaluates the consistency of various General Relativity and Modified Gravity cosmological models with high-redshift data, highlighting the importance of structure growth measurements in model discrimination.

Contribution

It provides a comprehensive comparison of multiple cosmological models using both background and structure growth data, employing parametric and non-parametric methods.

Findings

$F(Q)$, non-flat $ m{ extLambda}$CDM, and $ m{ extomega}$CDM models fit data well.

$F(R)$ models are strongly disfavored compared to $ m{ extLambda}$CDM.

$ m{ extLambda}$CDM remains the most preferred model based on BIC.

Abstract

Several models based on General Relativity and Modified Gravity aim to reproduce the observed universe with precision comparable to the flat-$\Lambda$CDM cosmological model. In this study, we investigate the consistency of some of these models with current high-redshift cosmic data, assessing their ability to simultaneously describe both the background expansion and matter clustering, using measurements of the Hubble parameter $H(z)$, the luminosity distance $D_L(z)$, and the growth rate of structures $[f\sigma_8](z)$ through parametric and non-parametric methods. Our results indicate that background observables alone offer limited capacity to distinguish between models, while the inclusion of growth of structures data proves useful in revealing deviations, even if small. An $F(Q)$ model, the non-flat $\Lambda$CDM and the $\omega$CDM emerge as alternatives well supported by data, closely matching the growth data and showing performance comparable to $\Lambda$CDM, as revealed by the Akaike Information Criterion. In contrast, $F(R)$ models are strongly disfavored compared to $\Lambda$CDM and $F(Q)$. However, according to the Bayesian Information Criterion, $\Lambda$CDM remains the preferred model among the models analysed. These analyses illustrate the usefulness of both parametric and non-parametric approaches to explore the observational viability of alternative cosmological models.