{ "id": "cond-mat/0402215", "version": "v1", "published": "2004-02-07T14:30:50.000Z", "updated": "2004-02-07T14:30:50.000Z", "title": "Random matrix ensembles from nonextensive entropy", "authors": [ "Fabricio Toscano", "Raul O. Vallejos", "Constantino Tsallis" ], "comment": "7 pages, including 3 PS figures", "doi": "10.1103/PhysRevE.69.066131", "categories": [ "cond-mat.stat-mech" ], "abstract": "The classical Gaussian ensembles of random matrices can be constructed by maximizing Boltzmann-Gibbs-Shannon's entropy, S_{BGS} = - \\int d{\\bf H} [P({\\bf H})] \\ln [P({\\bf H})], with suitable constraints. Here we construct and analyze random-matrix ensembles arising from the generalized entropy S_q = (1 - \\int d{\\bf H} [P({\\bf H})]^q)/(q-1) (thus S_1=S_{BGS}). The resulting ensembles are characterized by a parameter q measuring the degree of nonextensivity of the entropic form. Making q -> 1 recovers the Gaussian ensembles. If q \\ne 1, the joint probability distributions P(\\bf H) cannot be factorized, i.e., the matrix elements of \\bf H are correlated. In the limit of large matrices two different regimes are observed. When q<1, P(\\bf H) has compact support, and the fluctuations tend asymptotically to those of the Gaussian ensembles. Anomalies appear for q>1: Both P(\\bf H) and the marginal distributions P(H_{ij}) show power-law tails. Numerical analyses reveal that the nearest-neighbor spacing distribution is also long-tailed (not Wigner-Dyson) and, after proper scaling, very close to the result for the 2 x 2 case -- a generalization of Wigner's surmise. We discuss connections of these \"nonextensive\" ensembles with other non-Gaussian ones, like the so-called L\\'evy ensembles and those arising from soft-confinement.", "revisions": [ { "version": "v1", "updated": "2004-02-07T14:30:50.000Z" } ], "analyses": { "keywords": [ "random matrix ensembles", "nonextensive entropy", "analyze random-matrix ensembles", "joint probability distributions", "random matrices" ], "tags": [ "journal article" ], "publication": { "publisher": "APS", "journal": "Phys. Rev. E" }, "note": { "typesetting": "TeX", "pages": 7, "language": "en", "license": "arXiv", "status": "editable" } } }