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Related papers: Ces\`aro bounded operators in Banach spaces

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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

Every new inner product in a Hilbert space is obtained from the original one by means of a unique positive operator$.$ The first part of the paper is a survey on applications of such a technique, including a characterization of similarity…

Functional Analysis · Mathematics 2020-10-29 C. S. Kubrusly , B. P. Duggal

Following Berm\'udez et al. (ArXiv: 1706.03638v1), we study the rate of growth of the norms of the powers of a linear operator, under various resolvent conditions or Ces\`aro boundedness assumptions. We show that $T$ is power-bounded if…

Dynamical Systems · Mathematics 2020-10-13 Guy Cohen , Christophe Cuny , Tanja Eisner , Michael Lin

In this paper, we study {\it operator spaces\/} in the sense of the theory developed recently by Blecher-Paulsen [BP] and Effros-Ruan [ER1]. By an operator space, we mean a closed subspace $E\subset B(H)$, with $H$ Hilbert. We will be…

Functional Analysis · Mathematics 2016-09-06 Gilles Pisier

In this paper we completely characterize the norm attainment set of a bounded linear operator on a Hilbert space. This partially answers a question raised recently in [\textit{D. Sain, On the norm attainment set of a bounded linear…

Functional Analysis · Mathematics 2019-03-20 Debmalya Sain

Let $X$ be a complex Banach space. The connection between algebra homomorphisms defined on subalgebras of the Banach algebra $\ell^{1}(\mathbb{N}_0)$ and the algebraic structure of Ces\`{a}ro sums of a linear operator $T\in \mathcal{B}(X)$…

Functional Analysis · Mathematics 2015-04-07 Luciano Abadias , Carlos Lizama , Pedro J. Miana , M. Pilar Velasco

A bounded operator on a real or complex separable infinite-dimensional Banach space $Z$ is universal in the sense of Glasner and Weiss if for every invertible ergodic measure-preserving transformation $T$ of a standard Lebesgue probability…

Dynamical Systems · Mathematics 2015-12-18 Sophie Grivaux

In this paper we give growth estimates for $\|T^n\|$ for $n\to \infty$ in the case $T$ is a strongly Kreiss bounded operator on a UMD Banach space $X$. In several special cases we provide explicit growth rates. This includes known cases…

Functional Analysis · Mathematics 2025-08-12 Chenxi Deng , Emiel Lorist , Mark Veraar

In this paper, for $p>1$ and $s>1$, we give a complete description of the boundedness and compactness of a Ces\`aro-like operator from the Besov space $B_p$ into a Banach space $X$ between the mean Lipschitz space $\Lambda^s_{1/s}$ and the…

Complex Variables · Mathematics 2023-05-05 Fangmei Sun , Fangqin Ye , Liuchang Zhou

We characterize bounded multiplication operators in weighted Dirichlet spaces that are power bounded, Ces\`{a}ro bounded and uniformly Kreiss. Moreover, we show the equivalence in such spaces between mean ergodicity and Ces\`{a}ro…

Complex Variables · Mathematics 2025-03-06 Antonio Bonilla , Daniel Seco

Let $A$ be an unbounded operator on a Banach space $X$. It is sometimes useful to improve the operator $A$ by extending it to an operator $B$ on a larger Banach space $Y$ with smaller spectrum. It would be preferable to do this with some…

Functional Analysis · Mathematics 2017-04-13 Charles J. K. Batty , Felix Geyer

The purpose of this note is to show that, if $\mcB$ is a uniformly convex Banach, then the dual space $\mcB'$ has a "Hilbert space representation" (defined in the paper), that makes $\mcB$ much closer to a Hilbert space then previously…

Functional Analysis · Mathematics 2015-07-31 Tepper L. Gill , Marzett Golden

In this paper, we extend the concept of absolutely Ces\`aro boundedness to the fractional case. We construct a weighted shift operator belonging to this class of operators, and we prove that if $T$ is an absolutely Ces\`{a}ro bounded…

Functional Analysis · Mathematics 2017-10-10 Luciano Abadias , Antonio Bonilla

Firmly nonexpansive operators arise naturally as resolvents of monotone operators and as generalizations of projections and proximal mappings in convex optimization and fixed point theory. While their iterates are known to converge weakly…

Optimization and Control · Mathematics 2026-05-26 Heinz H. Bauschke , Tran Thanh Tung

We show that any bounded operator $T$ on a separable, reflexive, infinite-dimensional Banach space $X$ admits a rank one perturbation which has an invariant subspace of infinite dimension and codimension. In the non-reflexive spaces, we…

Functional Analysis · Mathematics 2012-08-30 Alexey I. Popov , Adi Tcaciuc

Denote by $ B_X $ the unit ball of an infinite-dimensional complex Hilbert space $ X. $ Let $\psi \in H(B_X),$ the space of all holomorphic functions on the unit ball $B_X,$ $\varphi \in S(B_X)$ the set of holomorphic self-maps of $B_X. $…

Complex Variables · Mathematics 2022-04-13 Thai Thuan Quang

We prove a new criterion of weak hypercyclicity of a bounded linear operator on a Banach space. Applying this criterion, we solve few open questions. Namely, we show that if $G$ is a region of $\C$ bounded by a smooth Jordan curve $\Gamma$…

Functional Analysis · Mathematics 2012-10-12 Stanislav Shkarin

Recent results concerning the linear dynamics and mean ergodicity of compact operators in Banach spaces, together with additional new results, are employed to investigate various spectral properties of generalized Ces\`aro operators acting…

Functional Analysis · Mathematics 2024-10-22 Angela A. Albanese , José Bonet , Werner J. Ricker

We study order-to-weak continuous operators from an ordered Banach space to a normed space. It is proved that under rather mild conditions every order-to-weak continuous operator is bounded.

Functional Analysis · Mathematics 2026-03-12 Eduard Emelyanov

Sz.-Nagy's famous theorem states that a bounded operator $T$ which acts on a complex Hilbert space $\mathcal{H}$ is similar to a unitary operator if and only if $T$ is invertible and both $T$ and $T^{-1}$ are power bounded. There is an…

Functional Analysis · Mathematics 2016-04-05 György Pál Gehér
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