Results 11 to 20 of about 12,824 (262)

Compact and limited operators [PDF]

Mathematische Nachrichten, 2021
AbstractLet be a bounded linear operator between two real normed spaces. We characterize compactness of T in terms of differentiability of the Lipschitz functions defined on X with values in another normed space Z. Furthermore, using a similar technique we can also characterize finite rank operators in terms of differentiability of a wider class of ...
Mohammed Bachir, Gonzalo Flores, Sebastián Tapia‐García   +2 more
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Some Properties of Unbounded M-Weakly and Unbounded L-Weakly Compact Operators

Journal of Mathematics, 2023
We introduce the class of unbounded M-weakly compact operators and the class of unbounded L-weakly compact operators. We investigate some properties for this new classification of operators, and we study the relation between them and M-weakly compact and
Zahra Niktab, Kazem Haghnejad Azar, Razi Alavizadeh, Saba Sadeghi Gavgani   +3 more
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Interpolation of compact bilinear operators [PDF]

Bulletin of Mathematical Sciences, 2020
This paper is devoted to the study of the stability of the compactness property of bilinear operators acting on the products of interpolated Banach spaces.
Mieczysław Mastyło, Eduardo B. Silva
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Some characterizations of surjective operators on banach lattices [PDF]

Journal of Hyperstructures, 2018
The concepts of compact and weakly compact operators on Banach spaces are considered and investigated in several papers. In this paper, taking idea from this notations, we consider the concept surjective compact and weakly compact operators on Banach ...
Akbar Bahramnezhad, Kazem Haghnejad Azar
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Representing the Banach operator ideal of completely continuous operators; pp. 189–193 [PDF]

Proceedings of the Estonian Academy of Sciences, 2017
Let V ;W∞ and W be the operator ideals of completely continuous, weakly ∞-compact, and weakly compact operators, respectively. In a recent paper, William B. Johnson, Eve Oja, and the author proved that V = W∞ ◦W -1 (Johnson, W. B., Lillemets, R.,
Rauni Lillemets
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Hilbert-Schmidtness of weighted composition operators and their differences on Hardy spaces [PDF]

Opuscula Mathematica, 2020
Let \(u\) and \(\varphi\) be two analytic functions on the unit disk \(\mathbb{D}\) such that \(\varphi(\mathbb{D}) \subset \mathbb{D}\). A weighted composition operator \(uC_{\varphi}\) induced by \(u\) and \(\varphi\) is defined on \(H^2\), the Hardy ...
Ching-on Lo, Anthony Wai-keung Loh
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Compact covariance operators [PDF]

Proceedings of the American Mathematical Society, 1981
Let B be a real separable Banach space and R: i'->ia covariance operator. All representations of R in the form 2en ® e", (e", n > 1} c fi, are characterized. Necessary and sufficient conditions for R to be compact are ob- tained, including a generalization of Mercer's theorem. An application to character- istic functions is given. 1. Introduction.
Baker, Charles R., McKeague, Ian W.
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Erratum to: Compactness properties for operators dominated by AM-compact operators [PDF]

Proceedings of the American Mathematical Society, 2009
In [ibid. 135, No. 4, 1151--1157 (2007; Zbl 1118.47029)], the authors have characterized Banach lattices such that operators dominated by AM-compact operators are AM-compact; but there was an error in the proof of this characterization. In this note, they give a new and correct proof by using a new lemma.
Aqzzouz, Belmesnaoui, Elbour, Aziz
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Compact operators in TRO’s [PDF]

Proceedings of the American Mathematical Society, 2012
We give a geometric characterization of the elements of a ternary ring of operators (or simply, TRO) that can be represented as compact operators by a faithful representation of the TRO.
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Dynamics of a Compact Operator [PDF]

ISRN Mathematical Analysis, 2011
Let be a compact linear (or more generally affine) operator from a Banach space into itself. For each , the sequence of iterates , , 1, and its averages , 1, are either bounded or approach infinity.
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