On tau functions for orthogonal polynomials and matrix models

Fuente: arXiv
Saved in:
Bibliographic Details
Main Author: Blower, Gordon
Format: Preprint
Published: 2010
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866929509924601856
author Blower, Gordon
author_facet Blower, Gordon
contents Let v be a real polynomial of even degree, and let ρbe the equilibrium probability measure for v with support S; so that v(x)\geq 2\int \log |x-y| ρ(dy)+C_v for some constant C_v with support S. Then S is the union of finitely many bounded intervals with endpoints delta_j, and ρis given by an algebrais weight w(x) on S. The system of orthogonal polynomials for w gives rise to the Magnus--Schlesinger differential equations. This paper identifies the tau function of this system with the Hankel determinant det[\in x^{j+k}ρ(dx)] of ρ. The solutions of the Magnus--Schlesinger equations are realised by a linear system, which is used to compute the tau function in terms of a Gelfand--Levitan equaiton. The tau function is associated with a potential q and a scattering problem for the Schrodinger operator with potential q. For some algebro-geometric potentials, the paper solves the scattering problem in terms of linear systems. The theory extends naturally to elliptic curves and resolves the case where S has exactly two intervals.
format Preprint
id arxiv_https___arxiv_org_abs_1008_2352
institution arXiv
publishDate 2010
record_format arxiv
spellingShingle On tau functions for orthogonal polynomials and matrix models
Blower, Gordon
Classical Analysis and ODEs
60B20, 37K15
Let v be a real polynomial of even degree, and let ρbe the equilibrium probability measure for v with support S; so that v(x)\geq 2\int \log |x-y| ρ(dy)+C_v for some constant C_v with support S. Then S is the union of finitely many bounded intervals with endpoints delta_j, and ρis given by an algebrais weight w(x) on S. The system of orthogonal polynomials for w gives rise to the Magnus--Schlesinger differential equations. This paper identifies the tau function of this system with the Hankel determinant det[\in x^{j+k}ρ(dx)] of ρ. The solutions of the Magnus--Schlesinger equations are realised by a linear system, which is used to compute the tau function in terms of a Gelfand--Levitan equaiton. The tau function is associated with a potential q and a scattering problem for the Schrodinger operator with potential q. For some algebro-geometric potentials, the paper solves the scattering problem in terms of linear systems. The theory extends naturally to elliptic curves and resolves the case where S has exactly two intervals.
title On tau functions for orthogonal polynomials and matrix models
topic Classical Analysis and ODEs
60B20, 37K15
url https://arxiv.org/abs/1008.2352