Bianchi type-II, VIII and IX cosmological models in a modified theory of gravity with variable Lambda

摘要

Spatially homogeneous Bianchi type-II, VIII and IX perfect fluid cosmological models in f(R, T) modified theory of gravity have been investigated for a special choice of f (R, T) = f(1)(R)+f(2)(T) with f(1)(R)=lambda R-1 and f(2)(T) = lambda T-2. This special choice leads to a cosmological constant Lambda, which depends on stress energy tensor of matter source. To get the deterministic model of Universe, we assume that the expansion scalar (theta) in the model is proportional to shear scalar (sigma). This condition leads to relation between metric potentials, which yields a time dependent deceleration parameter. Various physical and geometrical features of the models are also discussed.