Results 31 to 40 of about 822,201 (162)
Weyl-Type Theorems of Upper Triangular Relation Matrices
MathematicsThe spectral theory of operator matrices has several applications in elasticity, quantum mechanics, fluid dynamics, and other fields of mathematical physics.
Yanyan Du, Junjie Huang
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Antibiotics, 2022 It is urgent to find new antibiotic classes against multidrug-resistant bacteria as the rate of discovery of new classes of antibiotics has been very slow in the last 50 years.
Pietro Picconi +3 more
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A Nonlinear Schrödinger Equation Resonating at an Essential Spectrum
Advances in Mathematical Physics, 2016 We consider the nonlinear Schrödinger equation -Δu+f(u)=V(x)u in RN. The potential function V satisfies that the essential spectrum of the Schrödinger operator -Δ-V is [0,+∞) and this Schrödinger operator has infinitely many negative eigenvalues ...
Shaowei Chen, Haijun Zhou
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Jaw Tremor Resulting in Broken Teeth: On the Essential Tremor Spectrum
Tremor and Other Hyperkinetic Movements, 2015 Background: Jaw tremors in essential tremor (ET) rarely represent anything other than a cosmetic concern. Phenomenology Shown: A case of an ET patient whose jaw tremor was severe enough to result in cracked teeth.
Nora C. Hernandez, Elan D. Louis
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Quantum systems at the brink: existence of bound states, critical potentials, and dimensionality
Forum of Mathematics, Sigma, 2023 One of the crucial properties of a quantum system is the existence of bound states. While the existence of eigenvalues below zero, that is, below the essential spectrum, is well understood, the situation of zero energy bound states at the edge of the ...
Dirk Hundertmark +2 more
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Compactness of the difference between the porous thermoelastic semigroup and its decoupled semigroup
Electronic Journal of Differential Equations, 2015 Under suitable assumptions, we prove the compactness of the difference between the porous thermoelastic semigroup and its decoupled one. This will be achieved by proving the norm continuity of this difference and the compactness of the difference ...
El Mustapha Ait Benhassi +3 more
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Self-Commutators of Composition Operators with Monomial Symbols on the Dirichlet Space
Abstract and Applied Analysis, 2011 Let 𝜑(𝑧)=𝑧𝑛,𝑧∈𝕌, for some positive integer 𝑛 and 𝐶𝜑 the composition operator on the Dirichlet space 𝒟 induced by 𝜑. In this paper, we completely determine the point spectrum, spectrum, essential spectrum, and essential norm of the operators 𝐶∗𝜑𝐶𝜑,𝐶𝜑𝐶∗𝜑 ...
A. Abdollahi, S. Mehrangiz
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Essential versus $\#$-spectrum for smooth diffeomorphisms [PDF]
Proceedings of the American Mathematical Society, 1985 \textit{J. W. Robbin} conjectured in his 1972 survey article [Bull. Am. Math. Soc. 78, 923-952 (1972; Zbl 0256.58008)] that the ''essential'' and {\#}-spectra are identical for all \(C^ 1-diffeomorphisms\). If so, the stability conjecture of S. Smale follows.
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Essential Spectrum of a Class of Riemannian Manifolds [PDF]
The Journal of Geometric Analysis, 2014 In this paper we consider a family of Riemannian manifolds, not necessarily complete, with curvature conditions in a neighborhood of a ray. Under these conditions we obtain that the essential spectrum of the Laplacian contains an interval. The results presented in this paper allow to determine the spectrum of the Laplace operator on unlimited regions ...
Monte, Luiz Antônio C. +1 more
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Essentially alpha-hyponormal operators with essential spectrum of area zero
Le Matematiche, 2010 We prove that essentially alpha-hyponormal operators with zero area of the essential spectrum are essentially normal.
Vasile Lauric
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