Results 1 to 10 of about 1,388 (218)
A Generalization of Hankel Operators [PDF]
Journal of Functional Analysis, 2002 The author studies so called \(\lambda\)-Hankel operators which are the solutions of the operator equation \(S^\ast X-XS=\lambda X\) where \(\lambda\) is a complex number and \(S\) is the unilateral forward shift. He investigates some of the properties of \(\lambda\)-Hankel operators such as: invertibility, spectra, finite rank and positivity.
Martı́nez-Avendaño, Rubén A.
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μ-Hankel operators on Hilbert spaces [PDF]
Opuscula Mathematica, 2021 A class of operators is introduced (\(\mu\)-Hankel operators, \(\mu\) is a complex parameter), which generalizes the class of Hankel operators. Criteria for boundedness, compactness, nuclearity, and finite dimensionality are obtained for operators of ...
Adolf Mirotin, Ekaterina Kuzmenkova
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Finite rank intermediate Hankel operators and the big Hankel operator [PDF]
International Journal of Mathematics and Mathematical Sciences, 2006 Let La2 be a Bergman space. We are interested in an intermediate Hankel operator HφM from La2 to a closed subspace M of L2 which is invariant under the multiplication by the coordinate function z.
Tomoko Osawa
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On Ptak's Generalization of Hankel Operators [PDF]
Czechoslovak Mathematical Journal, 2001 In 1997 Pták defined generalized Hankel operators as follows: Given two contractions T1 ∈ B(H1) and T2 ∈ B(H2), an operator X: H1 → H2 is said to be a generalized Hankel operator if T2X = XT ∗ 1 and X satisfies a boundedness condition that depends on the unitary parts of the minimal isometric dilations of T1 and T2.
Hernández Mancera, Carmen +1 more
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On Determinant Expansions for Hankel Operators [PDF]
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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Soliton Theory and Hankel Operators [PDF]
SIAM Journal on Mathematical Analysis, 2015 Soliton theory and the theory of Hankel (and Toeplitz) operators have stayed essentially hermetic to each other. This paper is concerned with linking together these two very active and extremely large theories. On the prototypical example of the Cauchy problem for the Korteweg-de Vries (KdV) equation we demonstrate the power of the language of Hankel ...
Sergei Grudsky, Alexei Rybkin
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Toeplitz versus Hankel: semibounded operators [PDF]
Opuscula Mathematica, 2018 Our goal is to compare various results for Toeplitz \(T\) and Hankel \(H\) operators. We consider semibounded operators and find necessary and sufficient conditions for their quadratic forms to be closable. This property allows one to define \(T\) and \(
Dmitri R. Yafaev
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Hankel Operators with Discontinuous Symbol [PDF]
Proceedings of the American Mathematical Society, 1977 Douglas’s localisation theory for Toeplitz operators is used to show that there exist certain Hankel operators with discontinuous symbols which do not lie in the C
Stephen Power
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Linearizing and Forecasting: A Reservoir Computing Route to Digital Twins of the Brain [PDF]
Advanced Science, Volume 13, Issue 28, 18 May 2026.A new approach uses simple neural networks to create digital twins of brain activity, capturing how different patterns unfold over time. The method generates and recovers key dynamics even from noisy data. When applied to fMRI, it predicts brain signals and reveals distinctive activity patterns across regions and individuals, opening possibilities for ...
Gabriele Di Antonio +3 more
wiley +2 more sources
Hankel Operators on Fock Spaces [PDF]
, 2013 We study Hankel operators on the weighted Fock spaces\ud Fp. The boundedness and compactness of these operators are characterized in terms of BMO and VMO, respectively. Along the way, we also study Berezin transform and harmonic conjugates on the plane.
Perala, A. +2 more
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