Exact Cosmology in Myrzakulov Gravity

Abstract

In this paper, we have investigated some exact cosmological models in Myrzakulov gravity using a flat Friedmann-Lematre-Robertson-Walker (FLRW) spacetime metric. We have considered the modified Lagrangian function as $F(R,T)=R+\lambda T$, where $R, T$ are respectively the Ricci curvature scalar and the torsion scalar with respect to non-special connection, and $\lambda$ is a model parameter. We have obtained two exact solutions in two different situations for the scale factor $a(t)$. Using this scale factor, we have obtained various geometrical parameters to investigate cosmological properties of the universe. We have obtained the best fit values of model parameters through the MCMC analysis of two types latest observational datasets like $H(z)$ and Pantheon SNe Ia samples, with $1-\sigma, 2-\sigma$ \& $3-\sigma$ regions. We have performed a comparative and relativistic study of geometrical and cosmological parameters. In model-I, we have found that the effective equation of state (EoS) parameter $\omega_{eff}$ varies in the range $-1\le\omega_{eff}\le0$ while in the model-II, it varies as $-1.031\le\omega_{eff}\le0$. We have found that both models are transit phase (decelerating to accelerating) universe with transition redshift in the range $0.6<z_{t}<0.8$ and present age of the universe $t_{0}\approx13.5$ Gyrs.