PDEs satisfied by extreme eigenvalues distributions of GUE and LUE
arXiv:1102.0402
Abstract
In this paper we study, the probability that all the eigenvalues of finite unitary ensembles lie in the interval . This is identical to the probability that the largest eigenvalue is less than and the smallest eigenvalue is greater than . It is shown that a quantity allied to , namely, in the Gaussian Unitary Ensemble (GUE) and in the Laguerre Unitary Ensemble (LUE) satisfy certain nonlinear partial differential equations for fixed , interpreting as a function of and . These partial differential equations maybe considered as two variable generalizations of a Painlevé IV and a Painlevé V system, respectively. As an application of our result, we give an analytic proof that the extreme eigenvalues of the GUE and the LUE, when suitably centered and scaled, are asymptotically independent.