Zeros of optimal polynomial approximants: Jacobi matrices and Jentzsch-type theorems
Catherine Bénéteau
University of South Florida, Tampa, USADmitry Khavinson
University of South Florida, Tampa, USAConstanze Liaw
University of Delaware, Newark, USADaniel Seco
Universidad Carlos III de Madrid, Leganés, SpainBrian Simanek
Baylor University, Waco, USA
Abstract
We study the structure of the zeros of optimal polynomial approximants to reciprocals of functions in Hilbert spaces of analytic functions in the unit disk. In many instances, we find the minimum possible modulus of occurring zeros via a nonlinear extremal problem associated with norms of Jacobi matrices. We examine global properties of these zeros and prove Jentzsch-type theorems describing where they accumulate. As a consequence, we obtain detailed information regarding zeros of reproducing kernels in weighted spaces of analytic functions.
Cite this article
Catherine Bénéteau, Dmitry Khavinson, Constanze Liaw, Daniel Seco, Brian Simanek, Zeros of optimal polynomial approximants: Jacobi matrices and Jentzsch-type theorems. Rev. Mat. Iberoam. 35 (2019), no. 2, pp. 607–642
DOI 10.4171/RMI/1064