LRS Bianchi type IV space-time with anisotropic fluid

Abstract

In this study, locally rotationally symmetric Bianchi type IV universe is considered in Einstein's general theory of relativity in the presence of a cosmic fluid with anisotropic pressure but without heat flux. For this shear-free model, assuming linear barotropic equation of state, the exact solution of the field equation is obtained for the values of equation of state parameter -2/3 and -1/3. It has been shown that the model, which mimics dark energy, has an accelerating expansion anisotropy at the early time and approaches isotropy as the cosmic time increases.