Results 11 to 20 of about 448 (45)
Composition operators from ℬα to QK type spaces
Journal of Function Spaces, Volume 6, Issue 1, Page 88-104, 2008., 2008 Suppose that ϕ is an analytic self‐map of the unit disk Δ. Necessary and sufficient condition are given for the composition operator Cϕf = fοϕ to be bounded and compact from α‐Bloch spaces to QK type spaces which are defined by a nonnegative, nondecreasing function k(r) for 0 ≤ r < ∞.
Jizhen Zhou, Miroslav Englis
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On composition operators in QK type spaces
Journal of Function Spaces, Volume 5, Issue 2, Page 103-122, 2007., 2007 Let p ≥ 1, q > −2 and let K : [0, ∞) → [0, ∞) be nondecreasing. With a different choice of p, q, K, the Banach space QK(p, q) coincides with many well‐known analytic function spaces. Boundedness and compactness of the composition operator Cφ from α‐Bloch space Bα into QK(p, q) are characterized by a condition depending only on analytic mapping φ : 𝔻 ...
Marko Kotilainen, Miroslav Englis
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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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Orthogonally additive and orthogonally multiplicative holomorphic functions of matrices [PDF]
, 2014 Let $H:M_m\to M_m$ be a holomorphic function of the algebra $M_m$ of complex $m\times m$ matrices. Suppose that $H$ is orthogonally additive and orthogonally multiplicative on self-adjoint elements.
Bu, Qingying +2 more
core +2 more sources
Extension of Zhu′s solution to Lotto′s conjecture on the weighted Bergman spaces
International Journal of Mathematics and Mathematical Sciences, Volume 2004, Issue 41, Page 2199-2203, 2004., 2004 We reformulate Lotto′s conjecture on the weighted Bergman space Aα2 setting and extend Zhu′s solution (on the Hardy space H2) to the space Aα2.
Abebaw Tadesse
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Block Toeplitz operators with frequency‐modulated semi‐almost periodic symbols
International Journal of Mathematics and Mathematical Sciences, Volume 2003, Issue 34, Page 2157-2176, 2003., 2003 This paper is concerned with the influence of frequency modulation on the semi‐Fredholm properties of Toeplitz operators with oscillating matrix symbols. The main results give conditions on an orientation‐preserving homeomorphism α of the real line that ensure the following: if b belongs to a certain class of oscillating matrix functions (periodic ...
A. Böttcher, S. Grudsky, I. Spitkovsky
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Geometric properties of composition operators belonging to Schatten classes
International Journal of Mathematics and Mathematical Sciences, Volume 26, Issue 4, Page 239-248, 2001., 2001 We investigate the connection between the geometry of the image domain of an analytic function mapping the unit disk into itself and the membership of the composition operator induced by this function in the Schatten classes. The purpose is to provide solutions to Lotto′s conjectures and show a new compact composition operator which is not in any of ...
Yongsheng Zhu
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A hyperbolic universal operator commuting with a compact operator [PDF]
, 2019 A Hilbert space operator is called universal (in the sense of Rota) if every operator on the Hilbert space is similar to a multiple of the restriction of the universal operator to one of its invariant subspaces.
Cowen, Carl C. +1 more
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Hermitian composition operators on Hardy-Smirnov spaces
Concrete Operators, 2017 Let Ω be an open simply connected proper subset of the complex plane and φ an analytic self map of Ω. If f is in the Hardy-Smirnov space defined on Ω, then the operator that takes f to f º φ is a composition operator.
Gunatillake Gajath
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Approximation and entropy numbers of composition operators
Concrete Operators, 2020 We give a survey on approximation numbers of composition operators on the Hardy space, on the disk and on the polydisk, and add corresponding new results on their entropy numbers, revealing how they are different.
Li Daniel +2 more
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