Results 21 to 30 of about 1,463 (129)
International Journal of Mathematics and Mathematical Sciences, Volume 2004, Issue 27, Page 1437-1445, 2004., 2004 We investigate the spectrum of the differential operator Lλ defined by the Klein‐Gordon s‐wave equation y″ + (λ − q(x)) 2y = 0, x ∈ ℝ+ = [0, ∞), subject to the spectral parameter‐dependent boundary condition y′(0) − (aλ + b)y(0) = 0 in the space L2(ℝ+), where a ≠ ±i, b are complex constants, q is a complex‐valued function.
Gülen Başcanbaz-Tunca
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On some properties of Banach operators. II
International Journal of Mathematics and Mathematical Sciences, Volume 2004, Issue 47, Page 2513-2515, 2004., 2004 Using the notion of a Banach operator, wehave obtained a decompositional property of aHilbert space, and the equality of two invertible boundedlinear multiplicative operators on a normed algebra with identity.
A. B. Thaheem, A. R. Khan
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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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A formula for the inner spectral radius
International Journal of Mathematics and Mathematical Sciences, Volume 2004, Issue 61, Page 3285-3290, 2004., 2004 This note presents an asymptotic formula for the minimum of the moduli of the elements in the spectrum of a bounded linear operator acting on Banach space X. This minimum moduli is called the inner spectral radius, and the formula established herein is an analogue of Gelfand′s spectral radius formula.
S. Mahmoud Manjegani
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Structure of n-quasi left m-invertible and related classes of operators
Demonstratio Mathematica, 2020 Given Hilbert space operators T,S∈B(ℋ)T,S\in B( {\mathcal H} ), let Δ\text{Δ} and δ∈B(B(ℋ))\delta \in B(B( {\mathcal H} )) denote the elementary operators ΔT,S(X)=(LTRS−I)(X)=TXS−X{\text{Δ}}_{T,S}(X)=({L}_{T}{R}_{S}-I)(X)=TXS-X and δT,S(X)=(
Duggal Bhagwati Prashad, Kim In Hyun
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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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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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Quantum Mechanics of Damped Systems II. Damping and Parabolic Potential Barrier [PDF]
, 2003 We investigate the resonant states for the parabolic potential barrier known also as inverted or reversed oscillator. They correspond to the poles of meromorphic continuation of the resolvent operator to the complex energy plane.
Balazs N. L. +6 more
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The Spectrum and fine spectrum of generalized Rhaly-Cesàro matrices on c_0 and c
, 2018 The generalized Rhaly Cesàro matrices Aα are the triangular matrix with nonzero entries ank = αn−k/(n+1) with α ∈ [0,1] . In [Proc. Amer. Math. Soc. 86 (1982), 405409], Rhaly determined boundedness, compactness of generalized Rhaly Cesàro matrices on 2 ...
M. Yıldırım +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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