Koopman Operator for Stability Analysis: Theory with a Linear--Radial Product Reproducing Kernel

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Tang, Wentao, Ye, Xiuzhen
Natura: Preprint
Pubblicazione: 2025
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866911255606853632
author Tang, Wentao
Ye, Xiuzhen
author_facet Tang, Wentao
Ye, Xiuzhen
contents Koopman operator, as a fully linear representation of nonlinear dynamical systems, if well-defined on a reproducing kernel Hilbert space (RKHS), can be efficiently learned from data. For stability analysis and control-related problems, it is desired that the defining RKHS of the Koopman operator should account for both the stability of an equilibrium point (as a local property) and the regularity of the dynamics on the state space (as a global property). To this end, we show that by using the product kernel formed by the linear kernel and a Wendland radial kernel, the resulting RKHS is invariant under the action of Koopman operator (under certain smoothness conditions). Furthermore, when the equilibrium is asymptotically stable, the spectrum of Koopman operator is provably confined inside the unit circle, and escapes therefrom upon bifurcation. Thus, the learned Koopman operator with provable probabilistic error bound provides a stability certificate. In addition to numerical verification, we further discuss how such a fundamental spectrum--stability relation would be useful for Koopman-based control.
format Preprint
id arxiv_https___arxiv_org_abs_2511_06063
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Koopman Operator for Stability Analysis: Theory with a Linear--Radial Product Reproducing Kernel
Tang, Wentao
Ye, Xiuzhen
Systems and Control
Dynamical Systems
Koopman operator, as a fully linear representation of nonlinear dynamical systems, if well-defined on a reproducing kernel Hilbert space (RKHS), can be efficiently learned from data. For stability analysis and control-related problems, it is desired that the defining RKHS of the Koopman operator should account for both the stability of an equilibrium point (as a local property) and the regularity of the dynamics on the state space (as a global property). To this end, we show that by using the product kernel formed by the linear kernel and a Wendland radial kernel, the resulting RKHS is invariant under the action of Koopman operator (under certain smoothness conditions). Furthermore, when the equilibrium is asymptotically stable, the spectrum of Koopman operator is provably confined inside the unit circle, and escapes therefrom upon bifurcation. Thus, the learned Koopman operator with provable probabilistic error bound provides a stability certificate. In addition to numerical verification, we further discuss how such a fundamental spectrum--stability relation would be useful for Koopman-based control.
title Koopman Operator for Stability Analysis: Theory with a Linear--Radial Product Reproducing Kernel
topic Systems and Control
Dynamical Systems
url https://arxiv.org/abs/2511.06063