On non-invariant hypersurfaces of a nearly hyperbolic Sasakian manifold

摘要

We consider a nearly hyperbolic Sasakian manifold equipped with (f, g, u, v,lambda)-structure and study non-invariant hypersurface of a nearly hyperbolic Sasakian manifold equipped with (f, g, u, v,lambda)-structure. We obtain some properties of nearly hyperbolic Sasakian manifold equipped with (f, g, u, v,lambda)-structure. Further, we find the necessary and sufficient conditions for totally umbilical non-invariant hypersurface with (f, g, u, v,lambda)-structure of nearly hyperbolic Sasakian manifold to be totally geodesic. We also calculate the second fundamental form of a non-invariant hypersurface of a nearly hyperbolic Sasakian manifold with (f, g, u, v,lambda)-structure under the condition when f is parallel.