Bianchi Type-I Bulk Viscous String Cosmological Model with a Dynamical Cosmological Term

Abstract

The Einstein field equations with a cosmological constant are analyzed for a Bianchi type-I universe in the presence of bulk viscosity. The analysis assumes that: the bulk viscosity coefficient is directly proportional to the expansion scalar ; the expansion scalar is directly proportional to the shear scalar  and the cosmological constant  is directly proportional to the Hubble parameter . The physical and cosmological implications of these solutions are presented along with a discussion.