Bianchi-Type VI₀ Bulk Viscous Fluid Models with Variable Gravitational and Cosmological Constants

Manoj K. Verma, Shri Ram

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DOI: 10.4236/am.2011.23041                

Abstract

This paper deals with Bianchi type VI0 anisotropic cosmological models filled with a bulk viscous cosmic fluid in the presence of time-varying gravitational and cosmological constant. Physically realistic solutions of Einstein's field equations are obtained by assuming the conditions 1) the expansion scalar is proportional to shear scalar 2) the coefficient of the bulk viscosity is a power function of the energy density and 3) the cosmic fluid obeys the barotropic equation of state. We observe that the corresponding models retain the well established features of the standard cosmology and in addition, are in accordance with recent type Ia supernovae observations. Physical behaviours of the cosmological models are also discussed.

Keywords

Bianchi VI₀, Cosmology, Bulk viscosity, Variable G and ?

Conflicts of Interest

The authors declare no conflicts of interest.

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