Transit cosmological models in $$F(R,{\bar{T}})$$ gravity theory

Abstract

AbstractIn the present paper, we investigate some exact cosmological models in $$F(R,{\bar{T}})$$ F ( R , T ¯ ) gravity theory. We have considered the arbitrary function $$F(R, {\bar{T}})=R+\lambda {\bar{T}}$$ F ( R , T ¯ ) = R + λ T ¯ where $$\lambda $$ λ is an arbitrary constant, $$R, {\bar{T}}$$ R , T ¯ are respectively, the Ricci-scalar curvature and the torsion. We have solved the field equations in a flat FLRW spacetime manifold for Hubble parameter and using the MCMC analysis, we have estimated the best fit values of model parameters with $$1-\sigma , 2-\sigma , 3-\sigma $$ 1 - σ , 2 - σ , 3 - σ regions, for two observational datasets like H(z) and Pantheon SNe Ia datasets. Using these best fit values of model parameters, we have done the result analysis and discussion of the model. We have found a transit phase decelerating-accelerating universe model with transition redshifts $$z_{t}=0.4438_{-0.0790}^{+0.1008}, 0.3651_{-0.0904}^{+0.1644}$$ z t = 0 . 4438 - 0.0790 + 0.1008 , 0 . 3651 - 0.0904 + 0.1644 . The effective dark energy equation of state varies as $$-1\le \omega _{de}\le -0.5176$$ - 1 ≤ ω de ≤ - 0.5176 and the present age of the universe is found as $$t_{0}=13.8486_{-0.0640}^{+0.1005}, 12.0135_{-0.2743}^{+0.6206}$$ t 0 = 13 . 8486 - 0.0640 + 0.1005 , 12 . 0135 - 0.2743 + 0.6206 Gyrs, respectively for two datasets.