Work

Contractive realization theory for the annulus and other intersections of disks on the Riemann sphere

Year: 2026

Type: article

Abstract: We develop contractive finite dimensional realizations for rational matrix functions of one variable on domains that are not simply connected, such as the annulus. The proof uses multivariable contractive realization results as well as abstract operator algebra techniques. Other results include new bounds for the Bohr radius of the bidisk and the annulus.

Source: Journal of Functional Analysis

DOI: 10.1016/j.jfa.2026.111346

Authors: Radomił Baran, Piotr Pikul, Hugo J. Woerdeman, Michał Wojtylak

Institutions: Jagiellonian University, Drexel University

Language: English

Topic: Holomorphic and Operator Theory

Subfield: Applied Mathematics

Field: Mathematics

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $3,250

Funders: National Science Foundation, Banff International Research Station for Mathematical Innovation and Discovery, Directorate for Mathematical and Physical Sciences