Results 11 to 20 of about 1,449 (134)
Resolvent estimates for 2-dimensional perturbations of plane Couette flow
Electronic Journal of Differential Equations, 2002 We present results concerning resolvent estimates for the linear operator associated with the system of differential equations governing 2 dimensional perturbations of plane Couette flow.
Pablo Braz e Silva
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Spectrum and Analytic Functional Calculus for Clifford Operators via Stem Functions
Concrete Operators, 2021 The main purpose of this work is the construction of an analytic functional calculus for Clifford operators, which are operators acting on certain modules over Clifford algebras.
Vasilescu Florian-Horia
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Spectral and Scattering Properties of Quantum Walks on Homogenous Trees of Odd Degree [PDF]
, 2020 For unitary operators U0, U in Hilbert spaces H0,H and identification operator J : H0 → H, we present results on the derivation of a Mourre estimate for U starting from a Mourre estimate for U0 and on the existence and completeness of the wave operators ...
R. T. Aldecoa
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Compact perturbations of operators with property (t)
Open Mathematics, 2021 Let ℋ{\mathcal{ {\mathcal H} }} be an infinite dimensional complex Hilbert space and ℬ(ℋ){\mathcal{ {\mathcal B} }}\left({\mathcal{ {\mathcal H} }}) the algebra of all bounded linear operators on ℋ{\mathcal{ {\mathcal H} }}.
Yu Xinling, Shi Weijuan, Ji Guoxing
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On the quasi-Fredholm and Saphar spectrum of strongly continuous Cosine operator function
Moroccan Journal of Pure and Applied Analysis, 2021 Let (C(t))t∈ be a strongly continuous cosine family and A be its infinitesimal generator. In this work, we prove that, if C(t) – coshλt is Saphar (resp. quasi-Fredholm) operator and λt /∉iπ, then A – λ2 is also Saphar (resp.
Boua Hamid
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Spectra of Weighted Composition Operators with Quadratic Symbols
Concrete Operators, 2022 Previously, spectra of certain weighted composition operators W ѱ, φ on H2 were determined under one of two hypotheses: either φ converges under iteration to the Denjoy-Wolff point uniformly on all of 𝔻 rather than simply on compact subsets, or φ is ...
Doctor Jessica +4 more
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Study of the property (bz) using local spectral theory methods
Arab Journal of Basic and Applied Sciences, 2023 For a bounded linear operator, by local spectral theory methods, we study the property [Formula: see text] which means that the difference of the approximate point spectrum with the upper semi-Fredholm spectrum coincides with the set of all finite-range ...
Elvis Aponte, Jose Soto, Ennis Rosas
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Simple study designs in ecology produce inaccurate estimates of biodiversity responses
Journal of Applied Ecology, Volume 56, Issue 12, Page 2742-2754, December 2019., 2019 We suggest that more investment in more robust designs is needed in ecology since inferences from simpler designs, even with large sample sizes may be misleading. Facilitating this requires longer‐term funding and stronger research–practice partnerships. We also propose ‘accuracy weights’ and demonstrate how they can weight studies in three recent meta‐
Alec P. Christie +6 more
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(A,m)-Symmetric commuting tuples of operators on a Hilbert space
Mathematical Inequalities & Applications, 2019 Let T = (T1, · · · ,Td) and A be a commuting d -tuple of operators and a positive operator on a complex Hilbert space, respectively. We introduce an (A,m) -symmetric commuting tuple of operators and characterize the joint approximate point spectrum of (A,
M. Chō, S. Mahmoud
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Gap localization of TE‐modes by arbitrarily weak defects
Journal of the London Mathematical Society, Volume 95, Issue 3, Page 942-962, June 2017., 2017 Abstract This paper considers the propagation of TE‐modes in photonic crystal waveguides. The waveguide is created by introducing a linear defect into a periodic background medium. Both the periodic background problem and the perturbed problem are modelled by a divergence type equation.
B. M. Brown +4 more
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