{ "id": "2404.04581", "version": "v1", "published": "2024-04-06T10:31:42.000Z", "updated": "2024-04-06T10:31:42.000Z", "title": "Entropic curvature not comparable to other curvatures -- or is it?", "authors": [ "Supanat Kamtue", "Shiping Liu", "Florentin Münch", "Norbert Peyerimhoff" ], "categories": [ "math.DG", "math.MG", "math.PR" ], "abstract": "In this paper we consider global $\\theta$-curvatures of finite Markov chains with associated means $\\theta$ in the spirit of the entropic curvature (based on the logarithmic mean) by Erbar-Maas and Mielke. As in the case of Bakry-\\'Emery curvature, we also allow for a finite dimension parameter by making use of an adapted $\\Gamma$ calculus for $\\theta$-curvatures. We prove explicit positive lower curvature bounds (both finite- and infinite-dimensional) for finite abelian Cayley graphs. In the case of cycles, we provide also an upper curvature bound which shows that our lower bounds are asymptotically sharp (up to a logarithmic factor). Moreover, we prove new universal lower curvature bounds for finite Markov chains as well as curvature perturbation results (allowing, in particular, to compare entropic and Bakry-\\'Emery curvatures). Finally, we present examples where entropic curvature differs significantly from other curvature notions like Bakry-\\'Emery curvature or Ollivier Ricci and sectional curvatures.", "revisions": [ { "version": "v1", "updated": "2024-04-06T10:31:42.000Z" } ], "analyses": { "subjects": [ "53C21", "60J10", "05C81" ], "keywords": [ "entropic curvature", "finite markov chains", "bakry-emery curvature", "universal lower curvature bounds", "finite abelian cayley graphs" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }