Results 221 to 230 of about 21,814 (260)

Factoring Compact Operators and Approximable Operators

Zeitschrift für Analysis und ihre Anwendungen, 1990
Our paper is concerned with two topics. The first one is represented by aversion of Figiel’s and Johnson’s theorem on the factorization of compact operators adapted to the framework of ordered Banach spaces. Namely, we prove that every compact operator from a Banach space to an ordered Banach space with closed generating cone (respectively, a Banaöh ...
Popovici, I. M., Vuza, D. T.
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On Reflexive Compact Operators

Canadian Journal of Mathematics, 1977
Let A be a compact operator on a separable Hilbert space . The aim of this paper is to investigate the relationship between the weak closure of the algebra of polynomials in A (denoted by U(A)) and its invariant subspace lattice Lat A.
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U-Closure Operators and Compactness

Applied Categorical Structures, 2005
In this paper the authors introduce a notion of compactness in the following way: Let \({\mathcal A}\) be a category, \(\chi \) a finitely complete category with a proper \((\varepsilon ,{\mathcal M})\)-factorization structure for morphisms and \(U:{\mathcal A}\rightarrow \chi \) a functor. A pair \((A,m)\) with \(A\) object of \({\mathcal A}\) and \(m:
Gabriele Castellini, Eraldo Giuli
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On Compact Perturbations of Operators

Canadian Journal of Mathematics, 1974
Recently R. G. Douglas showed [4] that if V is a nonunitary isometry and U is a unitary operator (both acting on a complex, separable, infinite dimensional Hilbert space ), then V — K is unitarily equivalent to V ⊕ U (acting on ⊕ ) where K is a compact operator of arbitrarily small norm.
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Compact operators

1997
Abstract We begin this part on spectral theory with a chapter on compact operators. These operators provide the abstract framework to treat integral equations. As was shown by F. Riesz, their spectral behavior is similar to that of operators on finite dimensional spaces.
Reinhold Meise, Dietmar Vogt
openaire   +1 more source

On unitary equivalence of compact operator tuples

Science China Mathematics, 2022
Rongwei Yang, Yang Rongwei
exaly  

Characterization of the condition spectrum of a compact operator

Journal of Analysis, 2021
S Veeramani
exaly  

An operator onL pwithout best compact approximation

Israel Journal of Mathematics, 1985
Y Benyamini, Benyamini Y
exaly  

Quantitative estimates for a new complex Durrmeyer operator in compact disks

Applied Mathematics and Computation, 2011
Sorin G Gal, Vijay Gupta
exaly  

COMPACT OPERATORS

2021
Christophe Cheverry, Nicolas Raymond
openaire   +1 more source