We first prove some results on invariant lightlike submanifolds of indefinite Sasakian manifolds. Then, we introduce a general notion of contact Cauchy-Riemann (CR) lightlike submanifolds and study the geometry of leaves of their distributions. We also study a class, namely, contact screen Cauchy-Riemann (SCR) lightlike submanifolds which include invariant and screen real subcases. Finally, we ...

We investigate some geometric aspects of lightlike hypersurfaces of indefinite Kenmotsu manifolds, tangent to the structure vector field, by paying attention to the geometry of leaves of integrable distributions. Theorems on parallel vector fields, Killing distribution, geodesibility of those leaves are obtained. The geometrical configuration of such lightlike hypersurfaces and leaves of its sc...

This work delves into the space-time theory of 4-dimensional Kaehler manifold. Since isotropic pressure, energy density, and momentum tensor all vanish in a perfect fluid manifold, we have established that this manifold is an Einstein studied equation with cosmological constant it. Finally, demonstrated that, on conformally flat, perfectly velocity vector field infinitesimally spatially isotrop...