Results 1 to 10 of about 12,824 (262)

Commutators of compact operators.

Journal für die reine und angewandte Mathematik (Crelles Journal), 1977
In [4] Pearcy and Topping initiated the study of additive commutators of compact operators on Hilbert space and asked if each projection of rank one has this form. In [3] Brown and Schochet raised a more general question. Suppose H is an algebra of operators that contains the trace class operators and is commutative modulo the trace class operators. If
openaire   +3 more sources

Hyponormal differential operators with discrete spectrum [PDF]

Opuscula Mathematica, 2010
In this work, we first describe all the maximal hyponormal extensions of a minimal operator generated by a linear differential-operator expression of the first-order in the Hilbert space of vector-functions in a finite interval.
Zameddin I. Ismailov, Erdal Unluyol
doaj   +1 more source

A note on M-ideals in certain algebras of operators

International Journal of Mathematics and Mathematical Sciences, 2000
Let X=(∑n=1∞ℓ1n)p,   p>1. In this paper, we investigate M-ideals which are also ideals in L(X), the algebra of all bounded linear operators on X. We show that K(X), the ideal of compact operators on X is the only proper closed ideal in L(X) which is both
Chong-Man Cho, Woo Suk Roh
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On Compactness of Products of Toeplitz Operators

Complex Analysis and Operator Theory
Abstract We study compactness of product of Toeplitz operators with symbols continuous on the closure of the polydisc in terms of behavior of the symbols on the boundary. For certain classes of symbols f and g, we show that $$T_fT_g$$
Le, Trieu, Rodriguez, Tomas Miguel, Şahutoğlu, Sönmez   +2 more
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A Kastler-Kalau-Walze Type Theorem and the Spectral Action for Perturbations of Dirac Operators on Manifolds with Boundary

Abstract and Applied Analysis, 2014
We prove a Kastler-Kalau-Walze type theorem for perturbations of Dirac operators on compact manifolds with or without boundary. As a corollary, we give two kinds of operator-theoretic explanations of the gravitational action on boundary.
Yong Wang
doaj   +1 more source

Generalized Composition Operators Between Weighted Dirichlet Type Spaces and Bloch Type Spaces

Journal of Mathematical Extension, 2012
We characterize bounded and compact generalized composition operators between Bloch type spaces and weighted Dirichlet type spaces. Then, we show that these results can be employed to characterize bounded and compact Volterra type operators between ...
Sh. Rezaei∗, H. Mahyar
doaj  

Interpolation of compact non-linear operators

Journal of Inequalities and Applications, 2000
Let and be two Banach couples and let be a continuous map such that is a Lipschitz compact operator and is a Lipschitz operator. We prove that if is also compact or is continuously embedded in or is continuously embedded in , then is also a ...
Bento AJG
doaj  

Gudder–Nagy’s Theorem for Hilbert K(H)-Modules

Journal of Mathematics
We show in this paper Gudder–Nagy’s theorem for operators on Hilbert C∗-modules over C∗-algebra of compact operators. Let H be a complex Hilbert space with dim H>1, and KH the C∗-algebra of compact operators on H.
Ming-Hsiu Hsu
doaj   +1 more source

单位球上βP空间到Zα型空间的加权Cesàro算子(Extended Cesàro operators from βP spaces to Zα spaces on the unit ball)

Zhejiang Daxue xuebao. Lixue ban, 2013
Boundary and compact of extended Cesàro operators from βP spaces to Zygmund type space in the unit ball are studied. With the methods of functional analysis and several complex variables, the necessary and sufficient conditions are given for extended ...
ZHAOYan-hui(赵艳辉)
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A Theory for Interpolation of Metric Spaces

Axioms
In this work, we develop an interpolation theory for metric spaces inspired by the real method of interpolation. These interpolation spaces preserve Lipschitz operators under certain conditions.
Robledo Mak’s Miranda Sette, Dicesar Lass Fernandez, Eduardo Brandani da Silva   +2 more
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