Some sufficient conditions for existence of hyperinvariant subspaces for operators intertwined with unitaries
Abstract
For a power bounded or polynomially bounded operator sufficient conditions for the existence of a nontrivial hyperinvariant subspace are given. The obtained hyperinvariant subspaces of have the form of the closure of the range of . Here is a singular inner function, if is polynomially bounded, or is an analytic in the unit disc function with absolutely summable Taylor coefficients and singular inner part, if is supposed to be power bounded only. Also, an example of a quasianalytic contraction is given. The quasianalytic spectral set of is not the whole unit circle , while . Proofs are based on results by Esterle, Kellay, Borichev and Volberg.
Keywords
Cite
@article{arxiv.1712.07075,
title = {Some sufficient conditions for existence of hyperinvariant subspaces for operators intertwined with unitaries},
author = {Maria F. Gamal'},
journal= {arXiv preprint arXiv:1712.07075},
year = {2018}
}
Comments
This is Studia Math., 246(2019), 133-166 enlarged in the following sense: all proofs of lemmas deleted are preserved here