Essential norms of the Neumann operator of the arithmetical mean [PDF]
Mathematica Bohemica, 2001 Summary: Let \(K\subset \mathbb R^m\) (\(m\geq 2\)) be a compact set; assume that each ball centered on the boundary \(B\) of \(K\) meets \(K\) in a set of positive Lebesgue measure. Let \({\mathcal C}_0^{(1)}\) be the class of all continuously differentiable real-valued functions with compact support in \(\mathbb R^m\) and denote by \(\sigma _m\) the ...
Josef Král, Dagmar Medková
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Essential pseudospectra and essential norms of band-dominated operators [PDF]
Journal of Mathematical Analysis and Applications, 2015 39 pages; minor changes and ...
Raffael Hagger, Marko Lindner, M. Seidel
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Journal of Inequalities and Applications, 2016 In this paper, we give some estimates of the essential norm for generalized weighted composition operators from the Bloch space to the Zygmund space. Moreover, we give a new characterization for the boundedness and compactness of the operator.
Qinghua Hu +3 more
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Essential norm of composition operators on Harmonic Bloch spaces
Filomat, 2022 In this paper we characterize essential norm of composition operators on the spaces of Harmonic Bloch functions. We obtain some upper and lower bounds for the essential norm of composition operators between Harmonic Bloch function spaces. In some cases we find exact value of the essential norm such as in Theorems 2.7 and 2.11. These results
Estaremi, Y., Esmaeili, S., Ebadian, A.
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The essential norm of a composition operator mapping into Qk type spaces [PDF]
Journal of Function Spaces and Applications, 2008 An asymptotic formula for the essential norm of the composition operator Cφ(f):=f∘φ, induced by an analytic self-map φ of the unit disc, mapping from the α-Bloch space ℬα or the Dirichlet type space Dαp into Qk(p,q) is established in terms of an integral
Marko Kotilainen, Jouni Rättyä
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Essential norm of an integral-type operator from ω-Bloch spaces to μ-Zygmund spaces on the unit ball [PDF]
Opuscula Mathematica, 2018 In this paper, we give an estimate for the essential norm of an integral-type operator from \(\omega\)-Bloch spaces to \(\mu\)-Zygmund spaces on the unit ball.
Juntao Du, Xiangling Zhu
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Essential norm estimates for the $\bar{\partial}$-Neumann operator on convex domains and worm domains [PDF]
, 2015 In the paper we give a lower estimate for the essential norm of the $\bar{\partial}$-Neumann operator on convex domains and worm domains of Diederich and Fornaess.
Z. C̆uc̆ković, Sonmez Sahutoglu
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Essential norm and compactness of the product of differentiation and composition operators on Bloch type spaces [PDF]
, 2016 In this paper, we give a complete characterization of the compactness of the product of differentiation and composition operators on Bloch type spaces and little Bloch type spaces.
Xiangling Zhu
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On the Essential Norm of Multiplications Operators Acting on Cesàro Sequence Spaces
Journal of Function Spaces, 2019 In this article, we establish an important property about the growth of sequences in the dual space of Cesàro sequence spaces. As a consequence of this fact, we calculate the measure of noncompactness or the essential norm of the multiplication operator ...
Julio C. Ramos-Fernández +2 more
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The essential norm of bounded diagonal infinite matrices acting on Banach sequence spaces [PDF]
Demonstratio MathematicaWe calculate the essential norm of bounded diagonal infinite matrices acting on Köthe sequence spaces. As a consequence of our result, we obtain a recent criteria for the compactness of multiplication operator acting on Köthe sequence spaces.
Fernández Julio C. Ramos +2 more
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