GRW-space-time and certain type of energy–momentum tensor

Abstract

In [9] author proved that 4-dimensional Lorentzian concircular structure [in brief (CS)4] space–time coincides with generalized Robertson Walker [in brief GRW] space–time. Consequently, to study perfect fluid (CS)4-spacetime obeying Einstein equation under various curvature restrictions on energy–momentum tensor like semi-symmetric, Ricci semi-symmetric etc. are equivalent to study that of perfect fluid GRW-spacetime obeying Einstein equation. The paper attempts to point out the curvature conditions for which the nature of the fluid in GRW-spacetime obeying Einstein equation is sometimes phantom barrier and some other time remains quintessence barrier (De and Ljubica, 2015).