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Exact solution of Einstein’s field equations is obtained for massive string cosmological model of Bianchi IIIspace-time using the technique given by Letelier (1983) in presence of perfect fluid and electromagnetic field.To get thedeterministic solution of the Geld equations the expansion θ in the model is considered as proportional to the eigen valueσ_2~2 of the shear tensor σ_i~j and also the fluid obeys the barotropic equation of state.It is observed that in early stage ofthe evolution of the universe string dominates over the particle whereas the universe is dominated by massive string atthe late time.It is also observed that the string phase of the universe disappears in our model because particle densitybecomes negative.Some physical and geometric properties of the model are also discussed.
Exact solution of Einstein’s field equations is obtained for massive string cosmological model of Bianchi III space-time using the technique given by Letelier (1983) in presence of perfect fluid and electromagnetic field. To get the defensministic solution of the Geld equations the expansion θ in the model is considered as proportional to the eigen value σ_2 ~ 2 of the shear tensor σ_i ~ j and also the fluid obeys the barotropic equation of state. It is observed that in early stage of the evolution of the universe string dominates over the particle while the universe is dominated by massive string atthe late time. It is also observed that the string phase of the universe disappears in our model because particle density becomes negative. Home physical and geometric properties of the model are also discussed.