Results 31 to 40 of about 4,389,123 (370)
Universal Sequences of Composition Operators
The Journal of Geometric Analysis, 2023 Let $G$ and $ $ be two planar domains. We give necessary and sufficient conditions on a sequence $( _n)$ of eventually injective holomorphic mappings from $G$ to $ $ for the existence of a function $f\in H( )$ whose orbit under the composition by $( _n)$ is dense in $H(G)$.
Charpentier, S., Mouze, Augustin
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Isometric multiplication operators and weighted composition operators of BMOA
Journal of Inequalities and Applications, 2021 Let u be an analytic function in the unit disk D $\mathbb{D}$ and φ be an analytic self-map of D $\mathbb{D}$ . We give characterizations of the symbols u and φ for which the multiplication operator M u $M_{u}$ and the weighted composition operator M u ,
Ligang Geng
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Extremal Non-Compactness of Composition Operators with Linear Fractional Symbol [PDF]
, 2005 We realize norms of most composition operators acting on the Hardy space with linear fractional symbol as roots of hypergeometric functions. This realization leads to simple necessary and sufficient conditions on the symbol to exhibit extremal non ...
Basor, Estelle L., Retsek, Dylan Q.
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Weighted composition operators as Daugavet centers [PDF]
, 2009 We investigate the norm identity $\|uC_\phi + T\| = \|u\|_\infty + \|T\|$ for classes of operators on $C(S)$, where $S$ is a compact Hausdorff space without isolated point, and characterize those weighted composition operators which satisfy this equation
Demazeux, Romain
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Hardy spaces of generalized analytic functions and composition operators
Concrete Operators, 2018 We present some recent results on Hardy spaces of generalized analytic functions on D specifying their link with the analytic Hardy spaces. Their definition can be extended to more general domains Ω . We discuss the way to extend such definitions to more
Pozzi Elodie
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Fredholm composition operators [PDF]
Proceedings of the American Mathematical Society, 1980 In this paper a necessary and sufficient condition for a composition operator C T {C_T} on L 2 [ 0 , 1 ] {L^2}[0,1] to be a Fredholm operator is given.
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Approximation numbers of weighted composition operators [PDF]
, 2016 We study the approximation numbers of weighted composition operators $f\mapsto w\cdot(f\circ\varphi)$ on the Hardy space $H^2$ on the unit disc. For general classes of such operators, upper and lower bounds on their approximation numbers are derived. For
Lechner, Gandalf +3 more
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Composition and Decomposition of Positive Linear Operators (VIII)
Axioms, 2023 In a series of papers, most of them authored or co-authored by H. Gonska, several authors investigated problems concerning the composition and decomposition of positive linear operators defined on spaces of functions.
Ana Maria Acu +2 more
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Iteration of Composition Operators on small Bergman spaces of Dirichlet series
Concrete Operators, 2018 The Hilbert spaces ℋw consisiting of Dirichlet series F(s)=∑n=1∞ann-s$F(s) = \sum\nolimits_{n = 1}^\infty {{a_n}{n^{ - s}}}$ that satisfty ∑n=1∞|an|2/wn 0 and {wn}n having average order (logj+n)α${(\log _j^ + n)^\alpha }$, that the composition operators ...
Zhao Jing
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Convergence estimates for some composition operators
Constructive Mathematical AnalysisThere are different methods available in literature to construct a new operator. One of the methods to construct an operator is the composition method.
Vijay Gupta
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