{ "id": "1306.5079", "version": "v1", "published": "2013-06-21T09:20:56.000Z", "updated": "2013-06-21T09:20:56.000Z", "title": "Comparison Theorems for Manifold with Mean Convex Boundary", "authors": [ "Jian Ge" ], "comment": "13pages. submitted", "categories": [ "math.DG" ], "abstract": "Let $M^n$ be an $n$-dimensional Riemannian manifold with boundary $\\partial M$. Assume that Ricci curvature is bounded from below by $(n-1)k$, for $k\\in \\RR$, we give a sharp estimate of the upper bound of $\\rho(x)=\\dis(x, \\partial M)$, in terms of the mean curvature bound of the boundary. When $\\partial M$ is compact, the upper bound is achieved if and only if $M$ is isometric to a disk in space form. A Kaehler version of estimation is also proved. Moreover we prove a Laplace comparison theorem for distance function to the boundary of Kaehler manifold and also estimate the first eigenvalue of the real Laplacian.", "revisions": [ { "version": "v1", "updated": "2013-06-21T09:20:56.000Z" } ], "analyses": { "keywords": [ "mean convex boundary", "upper bound", "mean curvature bound", "laplace comparison theorem", "dimensional riemannian manifold" ], "note": { "typesetting": "TeX", "pages": 13, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2013arXiv1306.5079G" } } }