Anisotropic universe with cosmic strings and bulk viscosity

Tripathy, Sunil Kumar; Behera, Dipanjali; Routray, Tushar Ranjan
January 2010
Astrophysics & Space Science;Jan2010, Vol. 325 Issue 1, p93
Academic Journal
Spatially homogeneous and anisotropic LRS Bianchi type-I string cosmological models are studied in the frame work of general relativity when the source for the energy momentum tensor is a bulk viscous fluid containing one dimensional strings. A barotropic equation of state for the pressure and density is assumed to get determinate solutions of the field equations. The bulk viscous pressure is assumed to be proportional to the energy density. The physical and kinematical properties of the models are discussed. The role of bulk viscosity in getting an inflationary phase in the universe is studied.


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