Power law cosmology in Gauss-Bonnet gravity with pragmatic analysis

TL;DR

This paper explores a power law $f(R,G)$ gravity model with observational data analysis, showing it aligns with standard cosmology, exhibits late-time acceleration, and satisfies key energy conditions, indicating its viability for describing cosmic evolution.

Contribution

The study introduces a new $f(R,G)$ gravity model with power law dependence on $G$, reconstructed from observational data using MCMC, and demonstrates its consistency with accelerated cosmic expansion.

Findings

Model aligns with $ ext{Lambda}$CDM and shows late-time acceleration.

Violates strong energy condition, indicating repulsive gravity.

Consistent with observational constraints and thermodynamic laws.

Abstract

In this study, we present an approach $ f(R, G) $ gravity incorporating power law in $ G $. To study the cosmic evolution of the universe given by the reconstruction of the Hubble parameter given by $ E(z) = \bigg( 1+\frac{z(\alpha+(1+z)^{\beta})}{2 \beta + 1} \bigg)^{\frac{3}{2 \beta}} $. Subsequently, we use various recent observational datasets of OHD, Pantheon, and BAO to estimate the model parameters $ H_0,~\alpha $, and $ \beta $ applying the Markov Chain Monte Carlo (MCMC) technique in the emcee package to establish the validity of the model. In our findings, we observe that our model shows consistency with standard $ \Lambda $CDM, transits from deceleration to acceleration, and enters the quintessence region in late times. The cosmological model satisfies necessary energy constraints, simultaneously violating the strong energy condition (SEC), indicating a repulsive nature and consistent with accelerated expansion. The cosmic evolution of the Hawking temperature and the total entropy for the various observational datasets also show the validity of the model. Thus, our established model demonstrates sufficient potential for explicitly describing cosmological models.