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Related papers: Shift invariant subspaces in the Bloch space

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Functions in backward shift invariant subspaces have nice analytic continuation properties outside the spectrum of the inner function defining the space. Inside the spectrum of the inner function, Ahern and Clark showed that under some…

Complex Variables · Mathematics 2010-12-21 Andreas Hartmann , William T. Ross

In this article we study invariance properties of shift-invariant spaces in higher dimensions. We state and prove several necessary and sufficient conditions for a shift-invariant space to be invariant under a given closed subgroup of…

Classical Analysis and ODEs · Mathematics 2010-02-08 Magalí Anastasio , Carlos Cabrelli , Victoria Paternostro

We present some old and new results on a class of invariant spaces of holomorphic functions on symmetric domains, both in their circular bounded realizations and in their unbounded realizations as Siegel domains of type II. These spaces…

Complex Variables · Mathematics 2026-04-21 Mattia Calzi

By a famous result, functions in backward shift invariant subspaces in Hardy spaces are characterized by the fact that they admit a pseudocontinuation a.e. on $\T$. More can be said if the spectrum of the associated inner function has holes…

Complex Variables · Mathematics 2008-10-22 Andreas Hartmann

We study the class of operators $S_{\alpha,\beta}$ obtained by compressing the Hardy shift on the parametric spaces $H^2_{\alpha, \beta}$ corresponding to the pair $\{\alpha,\beta\}$ satisfying $|\alpha|^2+|\beta|^2=1$. We show, for nonzero…

Functional Analysis · Mathematics 2024-05-28 Susmita Das

It is proved that a commutative algebra $A$ of operators in a reflexive real Banach space has an invariant subspace if each operator $T\in A$ satisfies the condition $$\|1- \varepsilon T^2\|_e \le 1 + o(\varepsilon) \text{ when }…

Functional Analysis · Mathematics 2016-12-20 Victor Lomonosov , Victor Shulman

For a shift operator $T$ with finite multiplicity acting on a separable infinite dimensional Hilbert space we represent its nearly $T^{-1}$ invariant subspaces in terms of invariant subspaces under the backward shift. Going further, given…

Functional Analysis · Mathematics 2020-10-14 Yuxia Liang , Jonathan R. Partington

We obtaine the full characterization of proper closed invariant subspaces of a generalized backward shift operator (Pommiez operator) in the Frechet space of all holomorphic functions on a simply connected domain $\Omega$ of the complex…

Functional Analysis · Mathematics 2021-08-23 Olga A. Ivanova , Sergej N. Melikhov , Yurii N. Melikhov

This paper characterises the subspaces of $H^2(\mathbb D)$ simultaneously invariant under $S^2 $ and $S^{2k+1}$, where $S$ is the unilateral shift, then further identifies the subspaces that are nearly invariant under both $(S^2)^*$ and…

Functional Analysis · Mathematics 2026-04-07 Yuxia Liang , Jonathan R. Partington

A complete characterization of nearly-invariant subspaces of finite defect for the backward shift operator acting on the Hardy space is provided in the spirit of Hitt and Sarason's theorem. As a corollary we describe the almost-invariant…

Functional Analysis · Mathematics 2019-05-21 Isabelle Chalendar , Eva A. Gallardo-Gutiérrez , Jonathan R. Partington

We construct continuous (and even invertible) linear operators acting on Banach (even Hilbert) spaces whose restrictions to their respective closed linear subspaces of chain recurrent vectors are not chain recurrent operators. This…

Functional Analysis · Mathematics 2025-04-03 Antoni López-Martínez , Dimitris Papathanasiou

In this paper we study subspaces which are invariant under squares and cubes (separately as well as jointly) of unicellular backward weighted shift operators on a separable Hilbert space. The finite-dimensional subspaces are characterized…

Functional Analysis · Mathematics 2022-05-03 Sneh Lata , Sushant Pokhriyal , Dinesh Singh

It is well known that the structure of nontrival invariant subspaces for the shift operator on the Bergman space is extremely complicated and very little is known about their specific structures, and that a complete description of the…

Functional Analysis · Mathematics 2019-03-26 Junfeng Liu

In Bergman and Dirichlet spaces, the shift operator is not an isometry, but it is a left invertible operator. In this paper we give conditions on the left invertible operators such that a operator version, in the sense of Rosenblum and…

Functional Analysis · Mathematics 2017-04-14 Laura Gavruta

The property of being shift invariant and being reflexive or transitive in the case of the space of (asymmetric) truncated Toeplitz operators, and the space of (asymmetric) dual truncated operators is investigated. Most of the results…

Functional Analysis · Mathematics 2022-03-18 M. Cristina Câmara , Kamila Kliś-Garlicka , Bartosz Łanucha , Marek Ptak

We represent closed subspaces of the Hardy space that are invariant under finite-rank perturbations of the backward shift. We apply this to classify almost invariant subspaces of the backward shift and represent a more refined version of…

Functional Analysis · Mathematics 2024-08-09 Soma Das , Jaydeb Sarkar

We determine the boundedness and compactness of a large class of operators, mapping from general Banach spaces of holomorphic functions into a particular type of spaces of functions determined by the growth of the functions, or the growth…

Functional Analysis · Mathematics 2017-03-16 Nina Zorboska

We describe the proper closed invariant subspaces of the integration operator when it acts continuously on countable intersections and countable unions of weighted Banach spaces of holomorphic functions on the unit disc or the complex…

Functional Analysis · Mathematics 2020-04-07 José Bonet , Antonio Galbis

While the spectral properties and invariant subspaces of compressed shifts on model spaces are well understood, their behaviour on nearly $S^*$-invariant subspaces, a natural generalization with weaker structural constraints, remains…

Functional Analysis · Mathematics 2026-03-06 Y. Liang , J. R. Partington

We introduce a class of linear bounded invertible operators on Banach spaces, called shift operators, which comprises weighted backward shifts and models finite products of weighted backward shifts and dissipative composition operators. We…

Dynamical Systems · Mathematics 2024-07-31 Maria Carvalho , Udayan B. Darji , Paulo Varandas