Commuting operators over Pontryagin spaces with applications to system theory
Functional Analysis
2018-06-29 v1 Complex Variables
Abstract
In this paper we extend vessel theory, or equivalently, the theory of overdetermined systems to the Pontryagin space setting. We focus on realization theorems of the various characteristic functions associated to such vessels. In particular, we develop an indefinite version of de Branges-Rovnyak theory over real compact Riemann surfaces. To do so, we use the theory of contractions in Pontryagin spaces and the theory of analytic kernels with a finite number of negative squares. Finally, we utilize the indefinite de Branges-Rovnyak theory on compact Riemann surfaces in order to prove a Beurling type theorem on indefinite Hardy spaces on finite bordered Riemann surfaces.
Cite
@article{arxiv.1806.10704,
title = {Commuting operators over Pontryagin spaces with applications to system theory},
author = {Daniel Alpay and Ariel Pinhas and Victor Vinnikov},
journal= {arXiv preprint arXiv:1806.10704},
year = {2018}
}