{ "id": "2010.00441", "version": "v1", "published": "2020-10-01T14:33:23.000Z", "updated": "2020-10-01T14:33:23.000Z", "title": "Regularity of the optimal sets for the second Dirichlet eigenvalue", "authors": [ "Dario Mazzoleni", "Baptiste Trey", "Bozhidar Velichkov" ], "comment": "25 pages", "categories": [ "math.AP", "math.OC", "math.SP" ], "abstract": "This paper is dedicated to the regularity of the optimal sets for the second eigenvalue of the Dirichlet Laplacian. Precisely, we prove that if the set $\\Omega$ minimizes the functional \\[ \\mathcal F_\\Lambda(\\Omega)=\\lambda_2(\\Omega)+\\Lambda |\\Omega|, \\] among all subsets of a smooth bounded open set $D\\subset \\mathbb{R}^d$, where $\\lambda_2(\\Omega)$ is the second eigenvalue of the Dirichlet Laplacian on $\\Omega$ and $\\Lambda>0$ is a fixed constant, then $\\Omega$ is equivalent to the union of two disjoint open sets $\\Omega_+$ and $\\Omega_-$, which are $C^{1,\\alpha}$-regular up to a (possibly empty) closed set of Hausdorff dimension at most $d-5$, contained in the one-phase free boundaries $D\\cap \\partial\\Omega_+\\setminus\\partial\\Omega_-$ and $D\\cap\\partial\\Omega_-\\setminus\\partial\\Omega_+$.", "revisions": [ { "version": "v1", "updated": "2020-10-01T14:33:23.000Z" } ], "analyses": { "subjects": [ "35R35", "49Q10", "47A75" ], "keywords": [ "second dirichlet eigenvalue", "optimal sets", "regularity", "dirichlet laplacian", "second eigenvalue" ], "note": { "typesetting": "TeX", "pages": 25, "language": "en", "license": "arXiv", "status": "editable" } } }