Results 11 to 20 of about 3,279,270 (293)
On essential norm of the Neumann operator [PDF]
Mathematica Bohemica, 1992 The author gives an estimate of the essential norm of the Neumann operator. It is shown that under a deformation of the domain investigated by a diffeomorphism, which is conformal on a precisely specified part of the boundary, for the given norm there exists a norm on the space of continuous functions on the boundary of the deformated domain such that ...
Medková, Dagmar
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Essential norm resolvent estimates and essential numerical range
Journal of Spectral TheoryThe main result of this paper are novel two-sided estimates of the essential resolvent norm for closed linear operators T . We prove that the growth of \|(T-\lambda)^{-1}\|_{\textup{e}}
Nicolas Hefti, Christiane Tretter
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Norm and Numerical Radius Inequalities for a Product of Two Linear Operators in Hilbert Spaces [PDF]
, 2006 The main aim of the present paper is to establish some norm and numerical radius inequalities for the composite operator BA under suitable assumptions for the transform Cα ,β (T) := (T∗ −α I)(β I−T) , where α ,β ∈ C and T ∈ B(H), of the operators ...
S. S. Dragomir +2 more
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Norms and essential norms of linear combinations of endomorphisms [PDF]
Transactions of the American Mathematical Society, 2004 We compute norms and essential norms of linear combinations of endomorphisms on uniform algebras.
Gorkin, Pamela, Mortini, Raymond
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A class of operator related weighted composition operators between Zygmund space [PDF]
AUT Journal of Mathematics and Computing, 2021 Let $\mathbb {D}$ be the open unit disk in the complex plane $\mathbb{C}$ and $H(\mathbb{D})$ be the set of all analytic functions on $\mathbb{D}$. Let $u, v\in H(\mathbb{D})$ and $\varphi$ be an analytic self-map of $\mathbb{D}$.
Ebrahim Abbasi
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Generalized Stević-Sharma operators from the minimal Möbius invariant space into Bloch-type spaces
Demonstratio Mathematica, 2023 The aim of this study is to investigate the boundedness, essential norm, and compactness of generalized Stević-Sharma operator from the minimal Möbius invariant space into Bloch-type space.
Guo Zhitao
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The essential spectrum, norm, and spectral radius of abstract multiplication operators
Concrete Operators, 2023 Let EE be a complex Banach lattice and TT is an operator in the center Z(E)={T:∣T∣≤λIfor someλ}Z\left(E)=\left\{T:| T| \le \lambda I\hspace{0.33em}\hspace{0.1em}\text{for some}\hspace{0.1em}\hspace{0.33em}\lambda \right\} of EE. Then, the essential norm ‖
Schep Anton R.
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Axioms, 2023 The boundedness of a sum-type operator between weighted-type spaces is characterized and its essential norm is estimated.
Stevo Stević, Sei-Ichiro Ueki
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Essential Norm of the Weighted Composition Operators Between Growth Space [PDF]
Sahand Communications in Mathematical AnalysisFor $\alpha>0$, the growth space $\mathcal{A}^{-\alpha}$ is the space of all function $f\in H(\DD)$ such that $$\left\|f\right\|_{\mathcal{A}^{-\alpha}}=\sup_{z\in\DD}\left(1-\left|z\right|^2\right)^\alpha \left|f(z)\right|
Ebrahim Abbasi, Mostafa Hassanlou
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Norms of a Product of Integral and Composition Operators between Some Bloch-Type Spaces
Axioms, 2023 We present some formulas for the norm, as well as the essential norm, of a product of composition and an integral operator between some Bloch-type spaces of analytic functions on the unit ball, in terms of given symbols and weights.
Stevo Stević
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