Bianchi Type V Universe with Bulk Viscous Matter and Time Varying Gravitational and Cosmological Constants

Abstract

Spatially homogeneous and anisotropic Bianchi type V space-time with bulk viscous fluid source and time varying gravitational constant $G$ and cosmological term $\Lambda$ are considered. Coefficient of bulk viscosity $\zeta$ is assumed as a simple linear function of Hubble parameter $H$ (i.e. $\zeta ={\zeta }_0+{\zeta }_{1}H$, where ${\zeta }_0$ and ${\zeta }_1$ are constants). The Einstein field equations are solved explicitly by using a law of variation for the Hubble parameter, which yields a constant value of deceleration parameter. Physical and kinematical parameters of the models are discussed. The models are found to be compatible with the results of astronomical observations.

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