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Related papers: Abstract Ces\`aro spaces: Integral representations

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For a separable rearrangement invariant space $X$ on $(0,\infty)$ of fundamental type we identify the set of all $p\in [1,\infty]$ such that $\ell^p$ is finitely represented in $X$ in such a way that the unit basis vectors of $\ell^p$…

Functional Analysis · Mathematics 2021-04-28 S. V. Astashkin

In this article, we conduct a comprehensive study on the continuity, compactness, and spectral properties of Rhaly operators and generalized Ces\`aro operators, acting on weighted null sequence spaces. We determine the point spectrum,…

Functional Analysis · Mathematics 2025-10-14 Jyoti Rani , Arnab Patra

We describe holomorphic functions and fractional powers of Ces\'{a}ro operators in $L^2(\mathbb{R})$, $L^2(\mathbb{R}_+)$, and $L^2[0,1]$. Logarithms of Ces\'{a}ro operators are introduced as well and their spectral properties are studied.…

Functional Analysis · Mathematics 2024-11-26 Adolf Mirotin

We investigate structure of the optimal domains for the Hardy-type operators including, for example, the classical Ces\`aro, Copson and Volterra operators as well as for some of their generalizations. We prove that, in some sense, the…

Functional Analysis · Mathematics 2022-07-27 Tomasz Kiwerski , Paweł Kolwicz , Lech Maligranda

We consider the composition of operators with non-closed range in Hilbert spaces and how the nature of ill-posedness is affected by their composition. Specifically, we study the \mbox{Hausdorff-,} Ces\`{a}ro-, integration operator, and…

Functional Analysis · Mathematics 2024-05-17 Stefan Kindermann , Bernd Hofmann

The spectrum of the Ces\`aro operator $\mathsf{C}$ is determined on the spaces which arises as intersections $A^p_{\alpha +}$ (resp. unions $A^p_{\alpha -}$) of Bergman spaces $A_\alpha^p$ of order $1<p<\infty$ induced by standard radial…

Functional Analysis · Mathematics 2021-05-06 Ersin Kızgut

For the weight function $\prod_{i=1}^{d+1}|x_i|^{2\k_i}$ on the unit sphere, sharp local estimates of the orthogonal projection operators are obtained and used to prove the convergence of the Ces\`aro $(C,\delta)$ means in the weighted…

Classical Analysis and ODEs · Mathematics 2007-06-07 Feng Dai , Yuan Xu

We establish complete characterizations of various notions of expansivity for weighted composition operators on a very general class of locally convex spaces of continuous functions. This class includes several classical classes of…

Dynamical Systems · Mathematics 2025-12-09 Nilson C. Bernardes , Antonio Bonilla , João V. A. Pinto

Ces\`aro spaces are investigated from the optimal domain and optimal range point of view. There is a big difference between the cases on $[0, \infty)$ and on $[0, 1]$, as we can see in Theorem 1. Moreover, we present an improvement of Hardy…

Functional Analysis · Mathematics 2014-03-26 Karol Leśnik , Lech Maligranda

We characterize Ces\`aro-Orlicz function spaces $Ces_\varphi$ containing isomorphic copy of $l^\infty$. We also describe the subspaces $(Ces_\varphi)_a$ of all order continuous elements of $Ces_\varphi$. Finally, we study the monotonicity…

Functional Analysis · Mathematics 2022-07-27 Tomasz Kiwerski , Paweł Kolwicz

Cembranos and Freniche proved that for every two infinite compact Hausdorff spaces $X$ and $Y$ the Banach space $C(X\times Y)$ of continuous real-valued functions on $X\times Y$ endowed with the supremum norm contains a complemented copy of…

General Topology · Mathematics 2022-06-09 Jerzy Kąkol , Witold Marciszewski , Damian Sobota , Lyubomyr Zdomskyy

Conditions $C$, $C'$, and $C"$ were introduced for operator spaces in an attempt to study local reflexivity and exactness of operator spaces (Effros and Ruan, 2000). For example, it is known that an operator space $W$ is locally reflexive…

Operator Algebras · Mathematics 2012-09-11 Jung-Jin Lee

We investigate the isomorphic structure of the Ces\`aro spaces and their duals, the Tandori spaces. The main result states that the Ces\`aro function space $Ces_{\infty}$ and its sequence counterpart $ces_{\infty}$ are isomorphic, which…

Functional Analysis · Mathematics 2019-08-15 Sergey V. Astashkin , Karol Leśnik , Lech Maligranda

In this article we study the Ces\`{a}ro operator $$ \mathcal{C}(f)(z)=\frac{1}{z}\int_{0}^{z}f(\zeta)\,d\zeta, $$ and its companion operator $\mathcal{T}$ on Hardy spaces of the upper half plane. We identify $\mathcal{C}$ and $\mathcal{T}$…

Complex Variables · Mathematics 2010-06-09 Athanasios G. Arvanitidis , Aristomenis G. Siskakis

We study the question for which Tychonoff spaces $X$ and locally convex spaces $E$ the space $C_p(X,E)$ of continuous $E$-valued functions on $X$ contains a complemented copy of the space $(c_0)_p=\{x\in\mathbb{R}^\omega\colon x(n)\to0\}$,…

Functional Analysis · Mathematics 2023-06-29 Christian Bargetz , Jerzy Kąkol , Damian Sobota

In this paper we characterize spaces of continuous and $L^p$-functions on a compact Hausdorff space that are invariant under a transitive and continuous group action. This work generalizes Nagel and Rudin's 1976 results concerning unitarily…

Functional Analysis · Mathematics 2022-06-22 Samuel A. Hokamp

For a Tychonoff space $X$, let $C_k(X)$ and $C_p(X)$ be the spaces of real-valued continuous functions $C(X)$ on $X$ endowed with the compact-open topology and the pointwise topology, respectively. If $X$ is compact, the classic result of…

Functional Analysis · Mathematics 2018-09-25 Saak Gabriyelyan , Jerzy Kcakol

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

Ces\`aro $(C,\delta)$ means are studied for orthogonal expansions with respect to the weight function $\prod_{i=1}^{d}|x_i|^{2\k_i}$ on the unit sphere, and for the corresponding weight functions on the unit ball and the Jacobi weight on…

Classical Analysis and ODEs · Mathematics 2007-05-23 Feng Dai , Yuan Xu

Let $X$ be a compact Hausdorff space, let $E$ be a Banach space, and let $C(X,E)$ stand for the Banach space of $E$-valued continuous functions on $X$ under the uniform norm. In this paper we characterize Integral operators (in the sense of…

Functional Analysis · Mathematics 2009-09-25 Paulette Saab