Riemannian manifolds (M(sup n), g) of quasi-constant curvature

摘要

A Riemannian manifold (M(sup n), g) of quasi-constant curvature is defined. It is shown that an (M(sup n), g) in association with other class of manifolds gives rise, under certain conditions, to a manifold of quasi-constant curvature. Some observations on how a manifold of quasi-constant curvature accounts for a pseudo Ricci-symmetric manifold and quasi-umbilical hypersurface are made. (author). 10 refs. (Atomindex citation 26:077985)