{ "id": "1611.09877", "version": "v1", "published": "2016-11-29T21:09:21.000Z", "updated": "2016-11-29T21:09:21.000Z", "title": "Discontinuity of the phase transition for the planar random-cluster and Potts models with $q>4$", "authors": [ "Hugo Duminil-Copin", "Maxime Gagnebin", "Matan Harel", "Ioan Manolescu", "Vincent Tassion" ], "comment": "43 pages, 10 figures", "categories": [ "math.PR", "math-ph", "math.MP" ], "abstract": "We prove that the $q$-state Potts model and the random-cluster model with cluster weight $q>4$ undergo a discontinuous phase transition on the square lattice. More precisely, we show - Existence of multiple infinite-volume measures for the critical Potts and random-cluster models, - Ordering for the measures with monochromatic (resp. wired) boundary conditions for the critical Potts model (resp. random-cluster model), and - Exponential decay of correlations for the measure with free boundary conditions for both the critical Potts and random-cluster models. The proof is based on a rigorous computation of the Perron-Frobenius eigenvalues of the diagonal blocks of the transfer matrix of the six-vertex model, whose ratios are then related to the correlation length of the random-cluster model. As a byproduct, we rigorously compute the correlation lengths of the critical random-cluster and Potts models, and show that they behave as $\\exp(\\pi^2/\\sqrt{q-4})$ as $q$ tends to 4.", "revisions": [ { "version": "v1", "updated": "2016-11-29T21:09:21.000Z" } ], "analyses": { "subjects": [ "60K35", "82B20", "82B23", "82B26" ], "keywords": [ "random-cluster model", "planar random-cluster", "critical potts", "discontinuity", "correlation length" ], "note": { "typesetting": "TeX", "pages": 43, "language": "en", "license": "arXiv", "status": "editable" } } }