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arXiv · 2212.06526

Planar Orthogonal Polynomials as Type I Multiple Orthogonal Polynomials

Sergey Berezin·Arno B. J. Kuijlaars·Iván Parra
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Abstract

A recent result of S.-Y. Lee and M. Yang states that the planar orthogonal polynomials orthogonal with respect to a modified Gaussian measure are multiple orthogonal polynomials of type II on a contour in the complex plane. We show that the same polynomials are also type I orthogonal polynomials on a contour, provided the exponents in the weight are integer. From this orthogonality, we derive several equivalent Riemann-Hilbert problems. The proof is based on the fundamental identity of Lee and Yang, which we establish using a new technique.

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Sergey Berezin, Arno B. J. Kuijlaars, Iván Parra. 2022-12-13. Planar Orthogonal Polynomials as Type I Multiple Orthogonal Polynomials. https://doi.org/10.3842/sigma.2023.020

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