Gradient and Hessian Estimates for Dirichlet and Neumann Eigenfunctions
arXiv:1803.04233
Abstract
We establish integral formulas and sharp two-sided bounds for the Ricci curvature, mean curvature and second fundamental form on a Riemannian manifold with boundary. As applications, sharp gradient and Hessian estimates are derived for the Dirichlet and Neumann eigenfunctions.
15 pages