Cosmological Model with Time Varying Cosmological Constant, Quadratic Equation of State and Special form of Deceleration Parameter in f (R, T) Gravity

Abstract

In this paper, Bianchi-V space-time is considered with time varying cosmological constant and a quadratic equation of state , (Singh, G. P et al.: Astrophys. Space Sci. 360, 34, 2015) where is a constant in the frame work of gravity (Harko et al. in Phys.Rev. D 84:024020, 2011) where is an arbitrary function of Ricci scalar R and trace of the energy momentum tensor T. The Einstein’s field equations have been solved by taking into account the special form of deceleration parameter (Singha, A., Debnath, U.:Int.J. Theor. Phys. 48, 2009). We observe that in f(R, T) gravity, an extra acceleration is always present due to coupling between matter and geometry. The geometrical and physical aspect of the model is also studied. We find that the model has initial singularity and the physical parameters diverge at the initial epoch. The model resemble ΛCDM model for large time . The energy conditions of the model are also examined and found to be consistent with recent cosmological observations.