{ "id": "math-ph/0307055", "version": "v1", "published": "2003-07-28T09:28:25.000Z", "updated": "2003-07-28T09:28:25.000Z", "title": "Random matrices with external source and multiple orthogonal polynomials", "authors": [ "P. M. Bleher", "A. B. J. Kuijlaars" ], "comment": "17 pages", "journal": "Int.Math.Res.Not.2004:109-129,2004", "categories": [ "math-ph", "hep-th", "math.CA", "math.MP" ], "abstract": "We show that the average characteristic polynomial P_n(z) = E [\\det(zI-M)] of the random Hermitian matrix ensemble Z_n^{-1} \\exp(-Tr(V(M)-AM))dM is characterized by multiple orthogonality conditions that depend on the eigenvalues of the external source A. For each eigenvalue a_j of A, there is a weight and P_n has n_j orthogonality conditions with respect to this weight, if n_j is the multiplicity of a_j. The eigenvalue correlation functions have determinantal form, as shown by Zinn-Justin. Here we give a different expression for the kernel. We derive a Christoffel-Darboux formula in case A has two distinct eigenvalues, which leads to a compact formula in terms of a Riemann-Hilbert problem that is satisfied by multiple orthogonal polynomials.", "revisions": [ { "version": "v1", "updated": "2003-07-28T09:28:25.000Z" } ], "analyses": { "keywords": [ "multiple orthogonal polynomials", "external source", "random matrices", "average characteristic polynomial", "multiple orthogonality conditions" ], "tags": [ "journal article" ], "publication": { "doi": "10.1155/S1073792804132194" }, "note": { "typesetting": "TeX", "pages": 17, "language": "en", "license": "arXiv", "status": "editable", "inspire": 624472, "adsabs": "2003math.ph...7055B" } } }