Cosmological models with viscous fluid and variable deceleration parameter

Abstract

We obtain exact solutions of Einstein's field equations in the background of the spatially homogeneous and anisotropic Bianchi type-I space-time in the presence of a dissipative fluid with time-dependent cosmological “constant” \(\Lambda\) . Einstein's field equations are solved by taking the deceleration parameter q as a linear function of the Hubble parameter H. The universe shows a transition from an initial deceleration phase to the present accelerating phase. It is seen that the model approaches isotropy at late times. We discuss the jerk parameter j, which predicts that the universe in the model approaches the \( \Lambda\) CDM model at late times.