Characterizations of Twisted spacetimes

Abstract

The object of the present paper is to characterize pseudo Ricci symmetric twisted spacetimes.
At first it is shown that a pseudo Ricci symmetric twisted spacetime is a GRW spacetime. Next, we obtain a necessary and sufficient
condition for a pseudo Ricci symmetric twisted spacetime to be a perfect fluid spacetime. It is also proved that a pseudo Ricci symmetric
twisted spacetime is perfect fluid, provided the conformal curvature tensor is divergence free. Moreover, we investigate shear and vorticity vector fields
of such type of spacetimes and pointed out its implications towards the evolution of the Early Universe. Finally,
we study conformally flat $(PRS)_{n}$ spacetimes.