Bianchi Type-I Cosmology with Cosmic String and Bulk Viscosity

Some locally rotationally symmetric Bianchi type-I cosmological solutions for a cloud string with bulk viscosity are presented. In the first case, an equation of state ρ = kλ and the relation between metric potentials R = ASⁿ are considered, and the solution represents shearing non-rotating model with the bulk viscosity ∝ ρ^1/2, where ρ is the rest energy density of the cloud of strings with particles attached to them, λ is the tension density of the cloud of strings, is the coefficient of the bulk viscosity, R and S are only the functions of time t, while A and k are constant. In the second case, the constant coefficient of bulk viscosity is considered.