Results 21 to 30 of about 138 (121)
Bilinear Localization Operators on Modulation Spaces
Journal of Function Spaces, Volume 2018, Issue 1, 2018., 2018 We introduce a class of bilinear localization operators and show how to interpret them as bilinear Weyl pseudodifferential operators. Such interpretation is well known in linear case whereas in bilinear case it has not been considered so far.
Nenad Teofanov, Kasso A. Okoudjou
wiley +1 more source
Schatten-von Neumann classes of multilinear forms
Duke Mathematical Journal, 1992 The authors establish a number of results concerning normed ideals of multilinear forms in Banach spaces which extend the theory of trace ideals of operators on Hilbert space to such multilinear forms. For example, it is shown that the dual of the space of compact forms is the space of nuclear forms, while the second dual is the space of bounded forms.
Cobos, Fernando +2 more
openaire +3 more sources
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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Perturbations of Polynomials with Operator Coefficients
Journal of Complex Analysis, Volume 2013, Issue 1, 2013., 2013 We consider polynomials whose coefficients are operators belonging to the Schatten‐von Neumann ideals of compact operators in a Hilbert space. Bounds for the spectra of perturbed pencils are established. Applications to differential and difference equations are also discussed.
Michael Gil′, Janne Heittokangas
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The Calderón Reproducing Formula Associated with the Heisenberg Group Hd
Mathematical Problems in Engineering, Volume 2010, Issue 1, 2010., 2010 We establish the Calderón reproducing formula for functions in L2 on the Heisenberg group Hd. Also, we develop this formula in Lp(Hd) with 1 < p < ∞.
Jinsen Xiao, Jianxun He, Victoria Vampa
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Scattering theory for difference equations with operator coefficients
Journal of the London Mathematical Society, Volume 113, Issue 3, March 2026.Abstract We investigate a class of second‐order difference equations featuring operator‐valued coefficients with the aim of approaching problems of stationary scattering theory. We focus on various compact perturbations of the discrete Laplacian given in a Hilbert space of bi‐infinite square‐summable sequences with entries from a fixed Hilbert space ...
David Sher +3 more
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Maximal Regularity for Flexible Structural Systems in Lebesgue Spaces
Mathematical Problems in Engineering, Volume 2010, Issue 1, 2010., 2010 We study abstract equations of the form λu′′′(t) + u′′(t) = c2Au(t) + c2μAu′(t) + f(t), 0 < λ < μ which is motivated by the study of vibrations of flexible structures possessing internal material damping. We introduce the notion of (α; β; γ)‐regularized families, which is a particular case of (a; k)‐regularized families, and characterize maximal ...
Claudio Fernández +3 more
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Wavelet transform, Toeplitz type operators and decomposition of functions on the upper half-plane
Journal of Numerical Analysis and Approximation Theory, 1992 In this paper we consider the decomposition of functions on the upper half-plane into orthogonal subspaces which are isometric to \(L^{2}(\mathbb{R})\) by continuous wavelet transforms.
Ding-Xuan Zhou
doaj +2 more sources
Cybersecurity Driven Quantum Digital Twin for Proactive Threat Reversal in Open RAN
IET Quantum Communication, Volume 7, Issue 1, January/December 2026.This paper presents a novel cybersecurity‐driven quantum digital twin (CQDT) architecture for proactive defence in 6G Open RAN. By integrating quantum observables and reinforcement learning, the framework maintains high fidelity and suppresses entropy under adversarial CPTP noise. CQDT achieves real‐time adaptation with sub‐20 ms latency, meeting URLLC
Yassir Al‐Karawi +2 more
wiley +1 more source
Advances in Mathematical Physics, Volume 2009, Issue 1, 2009., 2009 For a system of n interacting particles moving in the background of a “homogeneous” potential, we show that if the single particle Hamiltonian admits a density of states, so does the interacting n‐particle Hamiltonian. Moreover, this integrated density of states coincides with that of the free particle Hamiltonian.
Frédéric Klopp +2 more
wiley +1 more source