A Bayesian Statistical Study of Bianchi Type-I Universe in $f(R,T^\psi)$ Modified Gravity

TL;DR

This paper investigates an anisotropic Bianchi Type-I universe model within $f(R,T^ psi)$ gravity, using Bayesian methods and observational data to constrain parameters and demonstrate compatibility with late-time cosmic acceleration.

Contribution

It applies Bayesian statistical techniques and MCMC analysis to constrain an extended gravity model with observational data, exploring anisotropic cosmology.

Findings

Model aligns with observational data and describes late-time acceleration.

Statistical analysis confirms model's stability and consistency.

Comparison with $ Lambda$CDM supports the model's reliability.

Abstract

We have examined the cosmological actions of LRS (Locally Rationally Symmetric) Bianchi type-I universe model in $f(R,T^\psi)$ gravity. For this, we have estimated the Hubble parameter, the effective equation of state parameter ($\omega^{eff}$), and the potential of the scalar field as a function of time using equation $H = W(\psi)$. The graphical representation of the potential function $V(\psi)$ with respect to cosmic time t is described. This study explores the dynamical properties of a Bianchi Type-I universe by utilizing Bayesian statistical techniques to constrain the model parameters and evaluate the viability of anisotropic cosmology under extended matter-geometry couplings. Also, we have applied the Markov Chain Monte Carlo (MCMC) mechanism on the derived $H(z)$ model by using observational Hubble data (OHD), the Baryon Acoustic Oscillation (BAO) dataset, and the Pantheon dataset. From the confidence-level contours and best-fit parameter values obtained, along with the corresponding reduced $\chi^{2}$, it is evident that the model aligns strongly with observational data, demonstrating statistical stability and consistency in describing late-time cosmic acceleration. Likewise, the error analyses presented in this research, including a comparison between the $\Lambda$CDM cosmology and the reconstructed $H(z)$ model, confirm the model's compatibility with current observations by yielding a reliable and accurate account of the universe's expansion history.