English
Related papers

Related papers: Frequently hypercyclic operators with irregularly …

200 papers

Let $S$ be a finitely generated abelian semigroup of invertible linear operators on a finite dimensional real or complex vector space $V$. We show that every coarsely dense orbit of $S$ is actually dense in $V$. More generally, if the orbit…

Functional Analysis · Mathematics 2013-02-20 Herbert Abels , Antonios Manoussos

Let $D$ be the differentiation operator $Df=f'$ acting on the Fr\'echet space $\H$ of all entire functions in one variable with the standard (compact-open) topology. It is known since 1950's that the set $H(D)$ of hypercyclic vectors for…

Functional Analysis · Mathematics 2012-09-06 Stanislav Shkarin

It is proved that, if $(P_n)$ is a sequence of polynomials with complex coefficients having unbounded valences and tending to infinity at sufficiently many points, then there is an infinite dimensional closed subspace of entire functions,…

Complex Variables · Mathematics 2025-01-17 L. Bernal-González , M. C. Calderón-Moreno , J. López-Salazar , J. A. Prado-Bassas

Certain operator algebras A on a Hilbert space have the property that every densely defined linear transformation commuting with A is closable. Such algebras are said to have the closability property. They are important in the study of the…

Functional Analysis · Mathematics 2009-08-10 H. Bercovici , R. G. Douglas , C. Foias , C. Pearcy

We introduce a class of (tuples of commuting) unbounded operators on a Banach space, admitting smooth functional calculi, that contains all operators of Helffer-Sj\"ostrand type and is closed under the action of smooth proper mappings.…

Spectral Theory · Mathematics 2016-08-16 Mats Andersson , Håkan Samuelsson , Sebastian Sandberg

If $T$ is a Kreiss bounded operator on a Banach space, then $\|T^n\|=O(n)$. Forty years ago Shields conjectured that in Hilbert spaces, $\|T^n\| = O(\sqrt{n})$. A negative answer to this conjecture was given by Spijker, Tracogna and Welfert…

Functional Analysis · Mathematics 2019-12-18 A. Bonilla , V. Müller

Relativizing an idea from multiplicity theory, we say that an element x of a von Neumann algebra M is n-divisible if (W*(x)' cap M) unitally contains a factor of type I_n. We decide the density of the n-divisible operators, for various n,…

Operator Algebras · Mathematics 2008-06-09 David Sherman

Well-bounded operators are linear operators on a Banach space $X$ that have an $AC[a,b]$ functional calculus for some interval $[a,b]$. A well-bounded operator is of type (B) if it can be written as an integral against a spectral family of…

Functional Analysis · Mathematics 2022-08-19 Alan Stoneham

We prove the spaceability of the set of hypercyclic vectors for {\em shifts-like operators}. Shift-like operators appear naturally as composition operators on $L^p(X)$, when the underlying space $X$ is dissipative. In the process of proving…

Functional Analysis · Mathematics 2023-09-06 Emma D'Aniello , Martina Maiuriello

In this paper we first introduce the extended limit set $J_{\{T^n\}}(x)$ for a sequence of bounded linear operators $\{T_n\}_{n=1}^{\infty}$ on a separable Banach space $X$ . Then we study the dynamics of sequence of linear operators by…

Functional Analysis · Mathematics 2017-03-10 M. R. Azimi

In this paper we study some dynamical properties such as Frequent Hypercyclicity Criterion, chaos, disjoint hypercyclicity and F-transitivity via Furstenberg family F for generalized bilateral weighted shift operator on the standard Hilbert…

Functional Analysis · Mathematics 2025-10-02 Song-Ung Ri , Hyon-Hui Ju , Jin-Myong Kim

It is well known that under certain conditions on a Banach space $X$, the set of bounded linear operators attaining their numerical radius is a dense subset. We prove in this paper that if $X$ is assumed to be uniformly convex and uniformly…

Functional Analysis · Mathematics 2023-02-28 Mohammed Bachir

An operator algebra $\mathcal{A}$ acting on a Hilbert space is said to have the closability property if every densely defined linear transformation commuting with $\mathcal{A}$ is closable. In this paper we study the closability property of…

Operator Algebras · Mathematics 2011-09-01 Hao-Wei Huang

For a power bounded or polynomially bounded operator $T$ sufficient conditions for the existence of a nontrivial hyperinvariant subspace are given. The obtained hyperinvariant subspaces of $T$ have the form of the closure of the range of…

Functional Analysis · Mathematics 2018-12-28 Maria F. Gamal'

We study Li-Yorke chaos for sequences of continuous linear operators from an \(F\)-space to a normed space. We introduce the \emph{D-phenomenon} to establish a common dense lineable criterion that encompasses properties such as recurrence,…

Functional Analysis · Mathematics 2025-02-06 Alexander Arbieto , Manuel Saavedra

A set $A \subseteq \mathbb{N}$ is a set of pointwise recurrence if for all minimal dynamical systems $(X, T)$, all $x \in X$, and all open neighborhoods $U \subseteq X$ of $x$, there exists a time $n \in A$ such that $T^n x \in U$. The set…

Dynamical Systems · Mathematics 2026-02-13 Daniel Glasscock , Anh N. Le

We prove that a continuous linear operator $T$ on a topological vector space $X$ with weak topology is mixing if and only if the dual operator $T'$ has no finite dimensional invariant subspaces. This result implies the characterization of…

Functional Analysis · Mathematics 2012-09-06 Stanislav Shkarin

We present a Banach space $\mathfrak X$ with a Schauder basis of length $\omega\_1$ which is saturated by copies of $c\_0$ and such that for every closed decomposition of a closed subspace $X=X\_0\oplus X\_1$, either $X\_0$ or $X\_1$ has to…

Functional Analysis · Mathematics 2007-05-23 Jordi Lopez Abad , Stevo Todorcevic

In this article, we address a problem posed by F. Bayart regarding the existence of an infinite-dimensional closed vector subspace (excluding the null operator) within the set of supercyclic operators on Banach spaces. We resolve this…

Functional Analysis · Mathematics 2024-03-28 Thiago R. Alves , Gustavo C. Souza

In this paper, we study frequent hypercyclicity for strongly continuous semigroups of operators $\left\{T_{t}\right\}_{t\in\Delta}$ indexed with complex sectors. We propose a revised and more natural definition of frequent hypercyclicity…

Functional Analysis · Mathematics 2025-03-04 Shengnan He , Zongbin Yin