{ "id": "1308.3606", "version": "v2", "published": "2013-08-16T11:29:25.000Z", "updated": "2013-10-04T20:04:52.000Z", "title": "On fractional Laplacians", "authors": [ "Roberta Musina", "Alexander I. Nazarov" ], "comment": "14 pages; this version is considerably enlarged", "categories": [ "math.AP" ], "abstract": "We compare two natural types of fractional Laplacians $(-\\Delta)^s$, \"Navier\" and \"Dirichlet\" ones. We show that for $0