Results 11 to 20 of about 185 (65)
Exterior products of operators and superoptimal analytic approximation
Transactions of the London Mathematical Society, 2021 We give a new algorithm for the construction of the unique superoptimal analytic approximant of a given continuous matrix‐valued function on the unit circle, using exterior powers of operators in preference to spectral or Wiener–Masani factorizations.
Dimitrios Chiotis +2 more
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On Determinant Expansions for Hankel Operators
Concrete Operators, 2020 Let w be a semiclassical weight that is generic in Magnus’s sense, and (pn)n=0∞({p_n})_{n = 0}^\infty the corresponding sequence of orthogonal polynomials. We express the Christoffel–Darboux kernel as a sum of products of Hankel integral operators.
Blower Gordon, Chen Yang
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Generalized Crofoot transform and applications
Concrete Operators, 2023 Matrix-valued asymmetric truncated Toeplitz operators are compressions of multiplication operators acting between two model spaces. These are the generalization of matrix-valued truncated Toeplitz operators. In this article, we describe symbols of matrix-
Khan Rewayat, Farooq Aamir
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Harmonic Hardy space and their operators
, 2020 Let H2 be the Hardy space on the unit disk. For inner functions u and v , the harmonic Hardy space H2 u,v is defined by H 2 u,v = uH 2 ⊕ vzH2 . Assume one of u and v is a nonconstant, then H2 u,v is a proper closed subspace of L 2(∂D) . We can define the
Xuanhao Ding, Yueshi Qin, Yuanqi Sang
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Hyponormal Toeplitz operators with polynomial symbols on weighted Bergman spaces
Journal of Inequalities and Applications, 2014 In this note we consider the hyponormality of Toeplitz operators Tφ on weighted Bergman space Aα2(D) with symbol in the class of functions f+g¯ with polynomials f and g.MSC:47B20, 47B35.
I. Hwang, Jongrak Lee, S. W. Park
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Functions of self‐adjoint operators in ideals of compact operators
Journal of the London Mathematical Society, Volume 95, Issue 1, Page 157-176, February 2017., 2017 Abstract For self‐adjoint operators A,B, a bounded operator J, and a function f:R→C, we obtain bounds in quasi‐normed ideals of compact operators for the difference f(A)J−Jf(B) in terms of the operator AJ−JB. The focus is on functions f that are smooth everywhere except for finitely many points. A typical example is the function f(t)=|t|γ with γ∈(0,1).
Alexander V. Sobolev
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Commutativity of Toeplitz operators on the Bergman spaces of the unit disk
, 2020 In this paper we give some necessary and sufficient conditions that Toeplitz operators with special symbols commute with Toeplitz operators with harmonic symbols on the Bergman space. Mathematics subject classification (2010): 47B35, 47B47.
C. Liu
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Lipschitz estimates for the Berezin transform
Journal of Function Spaces, Volume 8, Issue 2, Page 103-128, 2010., 2010 We consider the generalized Fock space A2(μm), where μm is the measure with weight e−|z|m, m > 0, with respect to the Lebesgue measure on Cn. Improving upon a recent result of L. Coburn and J. Xia, we show that for any bounded operator X on A2(μm) , the Berezin transform of X satisfies Lipschitz estimates.
Hélène Bommier-Hato, Miroslav Engliš
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Weighted integral Hankel operators with continuous spectrum
Concrete Operators, 2017 Using the Kato-Rosenblum theorem, we describe the absolutely continuous spectrum of a class of weighted integral Hankel operators in L2(ℝ+). These self-adjoint operators generalise the explicitly diagonalisable operator with the integral kernel sαtα(s ...
Fedele Emilio, Pushnitski Alexander
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Volterra composition operators from generalized weighted weighted Bergman spaces to µ‐Bloch spaces
Journal of Function Spaces, Volume 7, Issue 3, Page 225-240, 2009., 2009 Let φ be a holomorphic self‐map and g be a fixed holomorphic function on the unit ball B. The boundedness and compactness of the operator Tg,φf(z)=∫01f(φ(tz))ℜg(tz)dtt from the generalized weighted Bergman space into the µ‐Bloch space are studied in this paper.
Xiangling Zhu
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