Results 31 to 40 of about 332 (118)
Left and right generalized Drazin invertible operators on Banach spaces and applications
Operators and Matrices, 2019 In this paper, left and right generalized Drazin invertible operators on Banach spaces are defined and characterized by means of the generalized Kato decomposition. Then, new binary relations associated with these operators are presented and studied.
D. E. Ferreyra, F. Levis, N. Thome
semanticscholar +1 more source
Discrete Dynamics in Nature and Society, Volume 2004, Issue 1, Page 221-249, 2004., 2004 We present state of the art, the new results, and discuss open problems in the field of spectral analysis for a class of integral‐difference operators appearing in some nonequilibrium statistical physics models as collision operators. The author dedicates this work to the memory of Professor Ilya Prigogine, who initiated this activity in 1997 and ...
Yuri B. Melnikov
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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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Essential 𝒰cκ‐type maps and Birkhoff‐Kellogg theorems
International Journal of Stochastic Analysis, Volume 2004, Issue 1, Page 1-8, 2004., 2004 We present a new continuation theorem for 𝒰cκ‐type maps. The analysis is elementary and relies on properties of retractions and fixed point theory for self‐maps. Also we present some Birkhoff‐Kellogg type theorems on invariant directions.
R. P. Agarwal, Donal O′Regan
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General numerical radius inequalities for matrices of operators
Open Mathematics, 2016 Let Ai ∈ B(H), (i = 1, 2, ..., n), and T=[0⋯0A1⋮⋰A200⋰⋰⋮An0⋯0] $ T = \left[ {\matrix{ 0 & \cdots & 0 & {A_1 } \cr \vdots & {\mathinner{\mkern2mu\raise1pt\hbox{.}\mkern2mu \raise4pt\hbox{.}\mkern2mu\raise7pt\hbox{.}\mkern1mu}} & {A_2 } & 0
Al-Dolat Mohammed +3 more
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Approximate controllability of fractional differential equations via resolvent operators
Advances in Differential Equations, 2014 Of concern are the existence and approximate controllability of fractional differential equations governed by a linear closed operator which generates a resolvent.
Z. Fan
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Local spectral theory for 2 × 2 operator matrices
International Journal of Mathematics and Mathematical Sciences, Volume 2003, Issue 42, Page 2667-2672, 2003., 2003 We discuss the spectral properties of the operator MC ∈ ℒ(X ⊕ Y) defined by MC:=(AC0B), where A ∈ ℒ(X), B ∈ ℒ(Y), C ∈ ℒ(Y, X), and X, Y are complex Banach spaces. We prove that (SA∗∩SB)∪σ(MC)=σ(A)∪σ(B) for all C ∈ ℒ(Y, X). This allows us to give a partial positive answer to Question 3 of Du and Jin (1994) and generalizations of some results of Houimdi ...
H. Elbjaoui, E. H. Zerouali
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Spectral inclusions and stability results for strongly continuous semigroups
International Journal of Mathematics and Mathematical Sciences, Volume 2003, Issue 37, Page 2379-2387, 2003., 2003 We prove some spectral inclusions for strongly continuous semigroups. Some stability results are also established.
Abdelkader Elkoutri, Mohamed Aziz Taoudi
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Preservers of pseudo spectra of operator Jordan triple products
, 2016 Let H be an infinite-dimensional complex Hilbert space and let L (H ) be the algebra of all bounded linear operators on H . For ε > 0 and T ∈ L (H ) , let rε (T ) denote the ε -pseudo spectral radius of T .
M. Bendaoud, A. Benyouness, M. Sarih
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The spectrum of a class of almost periodic operators
International Journal of Mathematics and Mathematical Sciences, Volume 2003, Issue 36, Page 2277-2301, 2003., 2003 For almost Mathieu operators, it is shown that the occurrence of Cantor spectrum and the existence, for every point in the spectrum and suitable phase parameters, of at least one localized eigenfunction which decays exponentially are inconsistent properties.
Norbert Riedel
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