The Eigenproblem and Invariant Subspaces: Perturbation Theory
Ilse C. F. Ipsen · Birkhäuser Boston eBooks · 2010
In this collection of papers, Pete Stewart established the foundations for the perturbation theory of invariant subspaces. He introduced two crucial concepts that allow a systematic approach toward such a perturbation theory: subspace rotation and operator separation. These two concepts form the guiding principle in most of these papers.