Generalized lower characteristic involving measures of non-strict singularity
Topological Algebra and its Applications, 2023 This work establishes a connection between the class of generalized lower characteristic operators and [⋅]a{\left[\cdot ]}_{a} acting on a Banach space involving measures of non-strict singularity.
Baraket Sami +2 more
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B-Fredholm elements in primitive C*-algebras
Open Mathematics, 2022 Let A{\mathcal{A}} be a unital primitive C∗\ast -algebra. This article studies the properties of the B-Fredholm elements, the B-Weyl elements and the B-Browder elements in A{\mathcal{A}}. Particularly, this article describes the B-Fredholm element as the
Kong Yingying, Jiang Lining
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Intrinsic characterizations of perturbation classes on some Banach spaces [PDF]
, 2010 We investigate relationships between inessential operators and improjective operators acting between Banach spaces X and Y, emphasizing the case in which one of the spaces is a C(K) space.
Gonzalez, M. +2 more
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On new strong versions of Browder type theorems
Open Mathematics, 2018 An operator T acting on a Banach space X satisfies the property (UWΠ) if σa(T)∖ σSF+−$\begin{array}{} \sigma_{SF_{+}^{-}} \end{array} $(T) = Π(T), where σa(T) is the approximate point spectrum of T, σSF+−$\begin{array}{} \sigma_{SF_{+}^{-}} \end{array} $
Sanabria José +4 more
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On the closed range problem for composition operators on the Dirichlet space
Concrete Operators, 2019 We characterize closed range composition operators on the Dirichlet space for a particular class of composition symbols. The characterization relies on a result about Fredholm Toeplitz operators with BMO1 symbols, and with Berezin transforms of vanishing
Zorboska Nina
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EP Elements in Rings and in Semigroups with Involution and in C*-algebras [PDF]
, 2015 This work includes a survey of most of the results concerning EP elements in semigroups and rings with involution and in C*-algebras. 2010 Mathematics Subject Classification: Primary 46L05, 46J05, 46H05, 46H30, 47A05, 47A53, 47A60, 15A09, 15A33, 16A28 ...
Karanasios, Sotirios
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Certain properties of the essential spectra in Banach spaces [PDF]
, 2017 Paper presented at the 4th Strathmore International Mathematics Conference (SIMC 2017), 19 - 23 June 2017, Strathmore University, Nairobi, Kenya.Let X be an arbitrary Banach space, and L (X) be the set of all bounded linear operators on X.
Agure, J. O. +2 more
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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
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
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The basic propositions on defect numbers, root numbers and indices of linear operators [PDF]
, 2020 : In this work, we use the notion of the measure of noncompactness in order to establish some results concerning the class of semi-Fredholm and Fredholm operators.
Weidmann +13 more
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