Results 21 to 30 of about 5,552,302 (58)
, 2011 In this paper we use analytical methods for boundary integral operators (more precisely, pseudodifferential operators) together with symmetry arguments in order to treat harmonic wave diffraction problems in which the field does not depend on the third ...
T. Ehrhardt, A. P. Nolasco, F. Speck
semanticscholar +1 more source
Closable Hankel operators and moment problems
, 2019 In a paper from 2016 D. R. Yafaev considers Hankel operators associated with Hamburger moment sequences q_n and claims that the corresponding Hankel form is closable if and only if the moment sequence tends to 0.
Berg, Christian, Szwarc, Ryszard
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Factorization of some triangular matrix functions and its applications
, 2015 We consider defined on the real line R matrix functions with monomial terms of the form ceiλx on the main diagonal and one row, and with zero entries elsewhere.
Y. Karlovich +2 more
semanticscholar +1 more source
On compactness of the dbar-Neumann problem and Hankel operators
, 2011 Let $\D=\D_1\setminus \Dc_2$, where $\D_1$ and $\D_2$ are two smooth bounded pseudoconvex domains in $\C^n, n\geq 3,$ such that $\Dc_2\subset \D_1.$ Assume that the $\dbar$-Neumann operator of $\D_1$ is compact and the interior of the Levi-flat points in
Celik, Mehmet, Sahutoglu, Sonmez
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Toeplitz Quantization without Measure or Inner Product
, 2013 This note is a follow-up to a recent paper by the author. Most of that theory is now realized in a new setting where the vector space of symbols is not necessarily an algebra nor is it equipped with an inner product, although it does have a conjugation ...
Sontz, Stephen Bruce
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Hyponormal trigonometric Toeplitz operators
, 2013 We investigate hyponormal Toeplitz operators Tφ with trigonometric polynomial symbols φ via the Caratheodory-Schur Interpolation Problem. We present several formulae for computing the rank of the selfcommutator [T ∗ φ ,Tφ ] in the cases where Tφ is a ...
I. Hwang, An-Hyun Kim
semanticscholar +1 more source
Unbounded Hankel operators and moment problems
, 2019 We find simple conditions for a non-negative Hankel quadratic form to be closable. Under some mild a priori assumption on the associated moments these sufficient conditions turn out to be also necessary.
Yafaev, D. R.
core +3 more sources
On the best constants in Markov-type inequalities involving Gegenbauer norms with different weights
, 2011 The paper is concerned with best constants in Markov-type inequalities between the norm of a higher derivative of a polynomial and the norm of the polynomial itself.
A. Böttcher, P. Dörfler
semanticscholar +1 more source
On semibounded Toeplitz operators
, 2016 We show that a semibounded Toeplitz quadratic form is closable in the space $\ell^2({\Bbb Z}_{+})$ if and only if its matrix elemens are Fourier coefficients of an absolutely continuous measure.
Yafaev, D. R.
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The weighted composition operators on the large weighted Bergman spaces
, 2018 In this paper, we characterize bounded, compact or Schatten class weighted composition operators acting on Bergman spaces with the exponential type weights. Moreover, we give the proof of the necessary part for the boundedness of composition operators on
Park, Inyoung
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