Results 11 to 20 of about 44 (44)
Compact perturbations of operators with property (t)
Open Mathematics, 2021 Let ℋ{\mathcal{ {\mathcal H} }} be an infinite dimensional complex Hilbert space and ℬ(ℋ){\mathcal{ {\mathcal B} }}\left({\mathcal{ {\mathcal H} }}) the algebra of all bounded linear operators on ℋ{\mathcal{ {\mathcal H} }}.
Yu Xinling, Shi Weijuan, Ji Guoxing
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Remarks on hyponormal Toeplitz operators with nonharmonic symbols
Open Mathematics, 2023 In this article, we present some necessary or sufficient conditions for the hyponormality of Toeplitz operator Tφ{T}_{\varphi } on the Bergman space A2(D){A}^{2}\left({\mathbb{D}}).
Kim Sumin, Lee Jongrak
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Range-Kernel orthogonality and elementary operators on certain Banach spaces
Demonstratio Mathematica, 2021 The characterization of the points in Cp:1 ...
Bachir Ahmed +3 more
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Range-kernel weak orthogonality of some elementary operators
Open Mathematics, 2021 We study the range-kernel weak orthogonality of certain elementary operators induced by non-normal operators, with respect to usual operator norm and the Von Newmann-Schatten pp-norm (1 ...
Bachir Ahmed +2 more
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On hyponormality on a weighted annulus
Open Mathematics, 2021 In this work, we consider the hyponormality of Toeplitz operators on the Bergman space of the annulus with a logarithmic weight. We give necessary conditions when the symbol is of the form φ+ψ¯\varphi +\overline{\psi }, where φ\varphi and ψ\psi are ...
Sadraoui Houcine +2 more
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Concrete Operators, 2022 Let (X, 𝒜, μ) be a σ−finite measure space. A transformation ϕ : X → X is non-singular if μ ∘ ϕ−1 is absolutely continuous with respect with μ. For this non-singular transformation, the composition operator Cϕ: 𝒟(Cϕ) → L2(μ) is defined by Cϕf = f ∘ ϕ, f ∈
Zhou Hang
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International Journal of Mathematics and Mathematical Sciences, Volume 2003, Issue 31, Page 1993-2002, 2003., 2003 We introduce the concept of quasireducible operators. Basic properties and illustrative examples are considered in some detail in order to situate the class of quasireducible operators in its due place. In particular, it is shown that every quasinormal operator is quasireducible. The following result links this class with the invariant subspace problem:
C. S. Kubrusly
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On the largest analytic set for cyclic operators
International Journal of Mathematics and Mathematical Sciences, Volume 2003, Issue 30, Page 1899-1909, 2003., 2003 We describe the set of analytic bounded point evaluations for an arbitrary cyclic bounded linear operator T on a Hilbert space ℋ; some related consequences are discussed. Furthermore, we show that two densely similar cyclic Banach‐space operators possessing Bishop′s property (β) have equal approximate point spectra.
A. Bourhim
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Some versions of Anderson′s and Maher′s inequalities I
International Journal of Mathematics and Mathematical Sciences, Volume 2003, Issue 52, Page 3281-3297, 2003., 2003 We prove the orthogonality (in the sense of Birkhoff) of the range and the kernel of an important class of elementary operators with respect to the Schatten p‐class.
Salah Mecheri
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Generalized derivation modulo the ideal of all compact operators
International Journal of Mathematics and Mathematical Sciences, Volume 32, Issue 8, Page 501-506, 2002., 2002 We give some results concerning the orthogonality of the range and the kernel of a generalized derivation modulo the ideal of all compact operators.
Salah Mecheri, Ahmed Bachir
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