Theory And Applications Of One-Sided Coupled Operator Matrices
Marjeta Kramar, Delio Mugnolo, Rainer Nagel
TL;DR
The paper surveys the theory of one-sided coupled operator matrices (osc) as a unified framework for abstract initial-value problems with unbounded boundary feedbacks.It develops an osc framework, establishes a spectral transfer principle, and provides generator and positivity criteria for the resulting block-operator systems.It then applies the theory to initial-boundary value problems, including diffusion–transport systems with dynamical boundary conditions and a wave equation, proving well-posedness and, in many cases, exponential stability.The results yield practical tools for analyzing complex PDEs with boundary feedback by reducing them to tractable operator-matrix conditions.
Abstract
The theory of one-sided coupled operator matrices, recently introduced by K.-J. Engel, is an abstract framework for concrete initial value problems and allows complete information on well-posedness, and stability of solutions. These notes are meant as a survey on this rich theory, with a particular stress on applications to initial-boundary value problems with unbounded boundary feedbacks. A diffusion-transport system with dynamical boundary conditions is discussed, and its well-posedness and various other properties are investigated. As a by-product, the well-posedness of a wave equation with dynamical boundary condition is also obtained.
