English

A Katznelson-Tzafriri theorem for analytic Besov functions of operators

Functional Analysis 2024-09-10 v4

Abstract

Let TT be a power-bounded operator on a Banach space XX, A\mathcal{A} be a Banach algebra of bounded holomorphic functions on the unit disc D\mathbb{D}, and assume that there is a bounded functional calculus for the operator TT, so there is a bounded algebra homomorphism mapping functions fAf \in \mathcal{A} to bounded operators f(T)f(T) on XX. Theorems of Katznelson-Tzafriri type establish that limnTnf(T)=0\lim_{n\to\infty} \|T^n f(T)\| = 0 for functions fAf \in \mathcal{A} whose boundary functions vanish on the unitary spectrum σ(T)T\sigma(T)\cap \mathbb{T} of TT, or sometimes satisfy a stronger assumption of spectral synthesis. We consider the case when A\mathcal{A} is the Banach algebra B(D)\mathcal{B}(\mathbb{D}) of analytic Besov functions on D\mathbb{D}. We prove a Katznelson-Tzafriri theorem for the B(D)\mathcal{B}(\mathbb{D})-calculus which extends several previous results.

Keywords

Cite

@article{arxiv.2201.12076,
  title  = {A Katznelson-Tzafriri theorem for analytic Besov functions of operators},
  author = {Charles Batty and David Seifert},
  journal= {arXiv preprint arXiv:2201.12076},
  year   = {2024}
}

Comments

To appear in Journal of Operator Theory