On weakly B symmetric pseudo Riemannian manifolds and its applications

Abstract

The object of the present paper is to study weakly B symmetric manifolds (WBS)n. At first some geometric properties of (WBS)n(n > 2) have been studied. Finally, we consider (WBS)4 spacetimes. They turn out to be both perfect and imperfect fluids Robertson-Walker space-times : an equation of state is provided in the first case, and in the second the nature of the bulk viscosity pressure is pointed out. Also, we construct an example of a (WBS)4.