Index theorems for quantum graphs [PDF]
, 2007 In geometric analysis, an index theorem relates the difference of the numbers of solutions of two differential equations to the topological structure of the manifold or bundle concerned, sometimes using the heat kernels of two higher-order differential ...
Fulling, S. A. +2 more
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A Note on Property $(gb)$ and Perturbations [PDF]
, 2012 An operator T ∈ B(X) defined on a Banach space X satisfies property (gb) if the complement in the approximate point spectruma(T) of the upper semi-B-Weyl spectrumSBF + (T) coincides with the set (T) of all poles of the resolvent of T.
Qingping Zeng, H. Zhong
semanticscholar +1 more source
Zoochoric and hydrochoric maritime dispersal of the Opuntia monacantha (Willd.) Haw. (Cactaceae) [PDF]
Biotemas, 2012 Evolutionary adaptations in the morphology and physiology of cactus species have been associated to their mechanisms of dispersal and colonization. The dispersal mechanisms and modes of Opuntia monacantha (Willd.) Haw.
Angelo Martins Fraga +4 more
doaj
Gohberg lemma, compactness, and essential spectrum of operators on compact Lie groups
, 2013 In this paper we prove a version of the Gohberg lemma on compact Lie groups giving an estimate from below for the distance from a given operator to the set of compact operators on compact Lie groups.
Dasgupta, Aparajita, Ruzhansky, Michael
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Generalized weyl's theorem for algebraically quasi-paranormal operators
Journal of Inequalities and Applications, 2012 Let T or T* be an algebraically quasi-paranormal operator acting on a Hilbert space. We prove: (i) generalized Weyl's theorem holds for f(T) for every f ∈ H(σ (T)); (ii) generalized a-Browder's theorem holds for f(S) for every S ≺ T and f ∈ H(σ(S)); (iii)
I. An, Y. Han
semanticscholar +2 more sources
NOTE ON SOME OPERATOR EQUATIONS AND LOCAL SPECTRAL PROPERTIES
, 2016 In this paper we define Sk, j by the set of solutions (A,B) of the operator equations AkBj+1Ak = A2k+ j and BkAj+1Bk = B2k+ j . Then we observe the set Sk, j is increasing for all integers k 1 and j 0 .
I. An, Eungil Ko
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The index of a pair of pure states and the interacting integer quantum Hall effect
Forum of Mathematics, SigmaWe introduce the index ${\mathcal N}(\omega _1,\omega _2)$ of a pair of pure states on a unital C*-algebra, which is a generalization of the notion of the index of a pair of projections on a Hilbert space.
Sven Bachmann +2 more
doaj +1 more source
ᵀ2^*-algebras of Bergman type operators with continuous coefficients on polygonal domains
, 2015 Given α ∈ (0,2] , the C∗ -algebra AKα generated by the identity operator and by the Bergman and anti-Bergman projections acting on the Lebesgue space L(Kα) over the open sector Kα = { z = reiθ : r > 0, θ ∈ (0,πα) is studied.
Y. Karlovich
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A transmission problem for the Helmholtz equation with higher order boundary conditions
, 2015 The present paper deals with some properties for certain classes of Wiener-Hopf operators associated with a wave diffraction problem. This diffraction problem is mathematically modeled by the Helmholtz equation and higher order boundary conditions on an ...
Alberto Simões
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Essential spectra of some matrix operators by means of measures of weak noncompactness
, 2014 In this paper, we give some results concerning stability in the Fredholm theory via the concept of measures of weak noncompactness. These results are exploited to investigate the essential spectra of some matrix operators on Banach spaces.
Boulbeba Abdelmoumen
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