Hypersurfaces of E_s~4 with proper mean curvature vector

摘要

Submanifolds satisfying ΔH = λH are named by B. Y. Chen sub-manifolds with proper mean curvature vector. We prove that a hypersurface of the pseudo-Euclidean space E_s~4 with ΔH = λH and diagonalizable shape operator, has constant mean curvature.