Results 1 to 10 of about 5,552,302 (58)
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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Bounded and compact Hankel operators on the Fock-Sobolev spaces
Filomat, 2022 This paper focuses on the operator-theoretic properties (boundedness and compactness) of Hankel operators on the Fock-Sobolev spaces Fp,m in terms of symbols in BMO pr and VMO pr spaces, respectively, for a non-negative integers m, 1 ? p < ? and r > 0.
Anuradha Gupta, B. Gupta
semanticscholar +1 more source
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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Ranks of commutators of truncated Toeplitz operators on finite dimensional spaces
, 2021 We study the rank of commutator [Aη ,A∗η ] of truncated Toeplitz operators Aη and A∗η with several type of inner symbols η on the model space Hθ with finite Blaschke product θ . Mathematics subject classification (2010): Primary 47B35; Secondary 32A37.
Yong Chen, K. Izuchi, Y. J. Lee
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Mean Lipschitz spaces and a generalized Hilbert operator [PDF]
, 2017 If $\mu $ is a positive Borel measure on the interval $[0, 1)$ we let $\mathcal H_\mu $ be the Hankel matrix $\mathcal H_\mu =(\mu _{n, k})_{n,k\ge 0}$ with entries $\mu _{n, k}=\mu _{n+k}$, where, for $n\,=\,0, 1, 2, \dots $, $\mu_n$ denotes the moment ...
Merchán, Noel
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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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Hyponormal Toeplitz operators on the Bergman space
, 2017 A Hilbert space operator is hyponormal if T ∗T − TT ∗ is positive. We consider hyponormality of Toeplitz operators on the Bergman space with a symbol in the class of f + g where f is a monomial and g is a polynomial.
Houcine Sadraoui, M. Guediri
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Key recommendations for primary care from the 2022 Global Initiative for Asthma (GINA) update
npj Primary Care Respiratory Medicine, 2023 The Global Initiative for Asthma (GINA) was established in 1993 by the World Health Organization and the US National Heart Lung and Blood Institute to improve asthma awareness, prevention and management worldwide.
M. Levy +18 more
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On the weak limit of compact operators on the reproducing kernel Hilbert space and related questions
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2016 By applying the so-called Berezin symbols method we prove a Gohberg- Krein type theorem on the weak limit of compact operators on the non- standard reproducing kernel Hilbert space which essentially improves the similar results of Karaev [5]: We also in ...
Saltan Suna
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The Weiss conjecture on admissibility of observation operators for contraction semigroups [PDF]
, 2001 We prove the conjecture of George Weiss for contraction semigroups on Hilbert spaces, giving a characterization of infinite-time admissible observation functionals for a contraction semigroup, namely that such a functional C is infinite-time admissible ...
A. Simard +13 more
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