2023/05/30 by Xinyu Mu, Shulin Lyu, Mu, Xinyu +1
Chemistry · Physics and Astronomy · #15B52 #33E17 #42C05 #FOS: Physical sciences #Mathematical Physics (math-ph) #Molecular spectroscopy and chirality #Nonlinear Waves and Solitons #Quantum Mechanics and Non-Hermitian Physics
paper · pdf · doi:10.48550/arxiv.2305.18833
openalex publication_date 2023/05/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We study the Hankel determinant generated by a Gaussian weight with Fisher-Hartwig singularities of root type at tj, j=1,⋯ ,N. It characterizes a type of average characteristic polynomial of matrices from Gaussian unitary ensembles. We derive the ladder operators satisfied by the associated monic orthogonal polynomials and three compatibility conditions. By using them and introducing 2N auxiliary quantities \Rn,j, rn,j, j=1,⋯,N\, we build a series of difference equations. Furthermore, we prove that \Rn,j, rn,j\ satisfy Riccati equations. From them we deduce a system of second order PDEs satisfied by \Rn,j, j=1,⋯,N\, which reduces to a Painlevé IV equation for N=1. We also show that the logarithmic derivative of the Hankel determinant satisfies the generalized σ-form of a Painlevé IV equation.