Invariant subspaces of ℋ2of an annulus

Doubly Invariant Subspaces of Annulus Operators

Reducing Subspaces on the Annulus

We study reducing subspaces for an analytic multiplication operator Mzn on the Bergman space L 2 a(Ar) of the annulus Ar, and we prove that Mzn has exactly 2 reducing subspaces. Furthermore, in contrast to what happens for the disk, the same is true for the Hardy space on the annulus. Finally, we extend the results to certain bilateral weighted shifts, and interpret the results in the context o...

Invariant Subspaces, Quasi-invariant Subspaces, and Hankel Operators

In this paper, using the theory of Hilbert modules we study invariant subspaces of the Bergman spaces on bounded symmetric domains and quasi-invariant sub-spaces of the Segal–Bargmann spaces. We completely characterize small Hankel operators with finite rank on these spaces.

Perturbation of invariant subspaces ∗

We consider two different theoretical approaches for the problem of the perturbation of invariant subspaces. The first approach belongs to the standard theory. In that approach the bounds for the norm of the perturbation of the projector are proportional to the norm of perturbation matrix, and inversely proportional to the distance between the corresponding eigenvalues and the rest of the spect...

Continuation of invariant subspaces

In this work we consider implementation and testing of an algorithm for continuation of invariant subspaces.