Results 221 to 230 of about 12,960 (264)

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.
openaire   +2 more sources

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.
openaire   +2 more sources

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
openaire   +2 more sources

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.
openaire   +2 more sources

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

Minimal hermitian compact operators related to a C*-subalgebra of K(H)

Journal of Mathematical Analysis and Applications, 2022
, Lining Jiang
exaly  

On interpolation of weakly compact bilinear operators

Mathematische Nachrichten, 2022
Fernando Cobos
exaly  

Matrix transformations and compact operators on Catalan sequence spaces

Journal of Mathematical Analysis and Applications, 2021
Merve Ilkhan Kara, Emrah Evren Kara
exaly  

A remark on the approximation of p-compact operators by finite-rank operators

Journal of Mathematical Analysis and Applications, 2012
Eve Oja
exaly  

Triangularizability of Polynomially Compact Operators

Integral Equations and Operator Theory, 2005
Matjaz Konvalinka
exaly