{ "id": "math/0408173", "version": "v2", "published": "2004-08-12T22:07:31.000Z", "updated": "2004-09-22T13:48:55.000Z", "title": "Limits of dense graph sequences", "authors": [ "Laszlo Lovasz", "Balazs Szegedy" ], "comment": "27 pages; added extension of result (Sept 22, 2004)", "categories": [ "math.CO" ], "abstract": "We show that if a sequence of dense graphs has the property that for every fixed graph F, the density of copies of F in these graphs tends to a limit, then there is a natural ``limit object'', namely a symmetric measurable 2-variable function on [0,1]. This limit object determines all the limits of subgraph densities. We also show that the graph parameters obtained as limits of subgraph densities can be characterized by ``reflection positivity'', semidefiniteness of an associated matrix. Conversely, every such function arises as a limit object. Along the lines we introduce a rather general model of random graphs, which seems to be interesting on its own right.", "revisions": [ { "version": "v2", "updated": "2004-09-22T13:48:55.000Z" } ], "analyses": { "keywords": [ "dense graph sequences", "subgraph densities", "limit object determines", "graphs tends", "random graphs" ], "note": { "typesetting": "TeX", "pages": 27, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2004math......8173L" } } }