Results 1 to 10 of about 33 (33)
The Numerical Range of C*ψ Cφ and Cφ C*ψ
Concrete Operators, 2021 In this paper we investigate the numerical range of C*bφm Caφn and Caφn C*bφm on the Hardy space where φ is an inner function fixing the origin and a and b are points in the open unit disc.
Clifford John +2 more
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Disjoint diskcyclicity of weighted shifts
Open Mathematics, 2022 In this article, we will discuss disjoint diskcyclicity for finitely many operators acting on a separable, infinite dimensional Fréchet space XX. More precisely, we provide disjoint disk blow-up/collapse property and disjoint diskcyclicity criterion.
Wang Cui, Zhou Ze-Hua, Zhang Liang
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Simply connected topological spaces of weighted composition operators
Open Mathematics, 2020 In this paper, we prove that the topological spaces of nonzero weighted composition operators acting on some Hilbert spaces of analytic functions on the unit open ball are simply connected.
Tong Cezhong, Zhang Zhan, Xu Biao
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Spectra of Weighted Composition Operators with Quadratic Symbols
Concrete Operators, 2022 Previously, spectra of certain weighted composition operators W ѱ, φ on H2 were determined under one of two hypotheses: either φ converges under iteration to the Denjoy-Wolff point uniformly on all of 𝔻 rather than simply on compact subsets, or φ is ...
Doctor Jessica +4 more
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Hypercyclicity of Composition Operators on Orlicz Function Spaces
Moroccan Journal of Pure and Applied Analysis, 2020 In this paper, we discuss the hypercyclic properties of composition operators on Orlicz function spaces. We give some different conditions under which a composition operator on Orlicz spaces is hyper-cyclic or not. Similarly, multiplication operators are
Jafari F., Kamali Z.
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Weighted composition operators on Hardy–Smirnov spaces
Concrete Operators, 2022 Operators of type f → ψf ◦ φ acting on function spaces are called weighted composition operators. If the weight function ψ is the constant function 1, then they are called composition operators.
Matache Valentin
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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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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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