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arXiv · 2103.12114

Skew-orthogonal polynomials in the complex plane and their Bergman-like kernels

Gernot Akemann·Markus Ebke·Iván Parra
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Abstract

Non-Hermitian random matrices with symplectic symmetry provide examples for Pfaffian point processes in the complex plane. These point processes are characterised by a matrix valued kernel of skew-orthogonal polynomials. We develop their theory in providing an explicit construction of skew-orthogonal polynomials in terms of orthogonal polynomials that satisfy a three-term recurrence relation, for general weight functions in the complex plane. New examples for symplectic ensembles are provided, based on recent developments in orthogonal polynomials on planar domains or curves in the complex plane. Furthermore, Bergman-like kernels of skew-orthogonal Hermite and Laguerre polynomials are derived, from which the conjectured universality of the elliptic symplectic Ginibre ensemble and its chiral partner follow in the limit of strong non-Hermiticity at the origin. A Christoffel perturbation of skew-orthogonal polynomials as it appears in applications to quantum field theory is provided.

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Gernot Akemann, Markus Ebke, Iván Parra. 2021-03-22. Skew-orthogonal polynomials in the complex plane and their Bergman-like kernels. https://doi.org/10.1007/s00220-021-04230-8

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