Bulk Viscous Cosmological Model Research Articles

Bulk Viscous Cosmological Models with Variable G and Λ

Einstein's equations with variable gravitational and cosmological “constants” are considered in the presence of bulk viscosity for the spatially flat homogeneous and isotropic universe in a way which conserves the energy momentum tensor. A solution is found in which the cosmological term varies inversely with the square of time. Our approach is compared with that of Arbab.

Anisotropic, spatially homogeneous, bulk viscous cosmological model

An anisotropic, spatially homogeneous, bulk viscous model of the universe without shear viscosity is investigated. The exact solutions of the model are derived and some physical consequences of the model are discussed.

Bulk viscous cosmological model

Robertson—Walker cosmological models with bulkviscosity are investigated explicitly with equation of statep=(γ-1)e. In particular, the physical nature of the extreme cases, i.e., degenerate vacuum bulkviscous fluid model and bulkviscous stiff fluid model are studied in detail.