Barrow holographic dark energy model in $f(R, T)$ theory

Abstract

We consider a recently modified version of holographic dark energy, known as Barrow holographic dark energy, in the framework of \(f(R, T)\) gravity and consider a flat Friedmann-Lemaitre-Robertson-Walker line element for our study. We solve the field equations of the model to obtain the values of Hubble parameter and scale factor of the universe. We obtain the values of deceleration parameter and effective equation of state to discuss the evolution of the universe. Further, we constrain the model parameters using various data sets like type Ia supernova, observational Hubble data, SH0ES data etc. We use the Monte Carlo Markov Chain method to obtain the best fit values of the model parameters. We observe that the best fit present values of Hubble parameter \(H_{0}=67.764_{-1.354}^{+1.274}\) and \(H_{0}=70.440_{-0.869}^{+0.816}\), obtained for two different combinations of observational data, are in agreement with recent observations. We also constrain the case in which our model converts to the Barrow holographic dark energy model in general relativity and compare the results of both models. We compare the results with \(\Lambda \)-CDM model wherever required. We plot deceleration parameter against redshift parameter for best fit values of the model parameters. We observe a smooth phase transition of the universe from early time decelerated expansion to accelerated expansion which shows compatibility with recent observations. The values of equation of state parameter \(\omega _{h}\) of Barrow holographic dark energy are found to be \(-0.873_{-0.078}^{+0.115}\) and \(-0.866_{-0.130}^{+0.156}\), and age of the universe are found to be 14.09 \(Gyr\) and 15.43 \(Gyr\) for two combination of data sets for Barrow holographic dark energy model in \(f(R, T)\) gravity. Furthermore, we apply statefinder and \(Om\) diagnostic to discriminate our model from existing dark energy models.