Bianchi Type-III String Cosmological Model With Bulk Viscosity and Magnetic Field

The Bianchi type-III cosmological model for a cloud string in the presence of bulk viscosity and magnetic field are presented. To obtain the determinate model it is assumed that there is an equation of state ρ=kλ and the scalar of expansion is proportional to the shear scalar θ α σ, which leads to a relation between metric potentials B=mCⁿ. The physical and geometric aspects of the model are also discussed. The model describes a shearing non-rotating continuously expanding universe with a big-bang start. In the absence of magnetic field, it reduces to the string model with bulk viscosity that was previously given in the literature.