Constraints on multi-fluid cosmology in modified Gauss-Bonnet gravity models with different observational data sets

TL;DR

This paper investigates how modified Gauss-Bonnet gravity models affect large-scale structure growth in the universe, using observational data and MCMC analysis to constrain model parameters within a multi-fluid cosmology framework.

Contribution

It introduces a comprehensive analysis of multi-fluid cosmology in modified Gauss-Bonnet gravity, incorporating redshift-space distortion data and comparing multiple models with observational constraints.

Findings

Constraints on model parameters from observational data

Predictions of structure growth consistent with redshift-space distortion measurements

Best-fit values for Sigma_8 and other cosmological parameters

Abstract

In the present work, we incorporate redshift-space distortion measurement to investigate the growth of large scale structure within the framework of multi-fluid cosmology in the context of modified Gauss-Bonnet gravity. Using three different modified Gauss-Bonnet gravity models, we compare the predictions of modified Gauss-Bonnet gravity expansion history-through the Friedmann equation with Hubble and BAO data sets and constrain models parameters. Within the context of multi-fluid cosmology in modified Gauss-Bonnet gravity, we obtain the structure growth equation. This equation is then combined with Sigma_8 to get f_Sigma_8 predictions-which is compared with redshift-space distortion data to constrain models parameters to obtain best-fit values including Sigma_8. This involves performing a Markov Chain Monte Carlo (MCMC) analysis for these specific forms of modified Gauss-Bonnet models.