Some String Cosmological Universes Containing Dark Energy

Abstract

Here we have investigated on string cosmological model universe coupled with electromagnetic field to study the evolution of the universe, it is found that such a model contains dark energy which implies that dark energy is there in the universe from the very beginning of its evolution when the particles exhibits in the form of strings. Moreover there is possibility that dark energy dominated universe can contain in it highly contracted cosmic string.  Using suitable physical assumptions for different cases, the field equations are solved exactly. The physical and kinematical features of the models and the effects of electromagnetic field with many novel and interesting consequences are revealed through this work and discussed in some details. Here the bulk viscosity and electromagnetic field are found to play great roles in the evolution of universe which will be beneficial in further research works.