English

Orthogonal polynomials in the normal matrix model with two insertions

Classical Analysis and ODEs 2026-03-24 v1 Probability

Abstract

We consider orthogonal polynomials with respect to the weight z2+a2cNeNz2|z^2+a^2|^{cN}e^{-N|z|^2} in the whole complex plane. We obtain strong asymptotics and the limiting normalized zero counting measure (mother body) of the orthogonal polynomials of degree nn in the scaling limit n,Nn,N\to \infty such that nNt\frac{n}{N}\to t. We restrict ourselves to the case a22ca^2\geq 2c, cNcN integer, and t<tt<t^{*} where tt^{*} is a constant depending only on a,ca,c. Due to this restriction, the mother body is supported on an interval. We also find the two dimensional equilibrium measure (droplet) associated with the eigenvalues in the corresponding normal matrix model. Our method relies on the recent result that the planar orthogonal polynomials are a part of a vector of type I multiple orthogonal polynomials, and this enables us to apply the steepest descent method to the associated Riemann-Hilbert problem.

Keywords

Cite

@article{arxiv.2408.12952,
  title  = {Orthogonal polynomials in the normal matrix model with two insertions},
  author = {Mario Kieburg and Arno B. J. Kuijlaars and Sampad Lahiry},
  journal= {arXiv preprint arXiv:2408.12952},
  year   = {2026}
}

Comments

89 pages, 10 figures

R2 v1 2026-06-28T18:21:54.871Z