{ "id": "1712.00875", "version": "v1", "published": "2017-12-04T02:02:23.000Z", "updated": "2017-12-04T02:02:23.000Z", "title": "Ollivier Ricci curvature for general graph Laplacians: Heat equation, Laplacian comparison, non-explosion and diameter bounds", "authors": [ "Florentin Münch", "Radoslaw K. Wojciechowski" ], "categories": [ "math.DG" ], "abstract": "Discrete time random walks on a finite set naturally translate via a one-to-one correspondence to discrete Laplace operators. Typically, Ollivier curvature has been investigated via random walks. We first extend the definition of Ollivier curvature to general weighted graphs and then give a strikingly simple representation of Ollivier curvature using the graph Laplacian. Using the Laplacian as a generator of a continuous time Markov chain, we connect Ollivier curvature with the heat equation which is strongly related to continuous time random walks. In particular, we prove that a lower bound on the Ollivier curvature is equivalent to a certain Lipschitz decay of solutions to the heat equation. This is a discrete analogue to a celebrated Ricci curvature lower bound characterization by Renesse and Sturm. Our representation of Ollivier curvature via the Laplacian allows us to deduce a Laplacian comparison principle by which we prove non-explosion and improved diameter bounds.", "revisions": [ { "version": "v1", "updated": "2017-12-04T02:02:23.000Z" } ], "analyses": { "subjects": [ "53C21" ], "keywords": [ "general graph laplacians", "heat equation", "ollivier ricci curvature", "ollivier curvature", "diameter bounds" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }