Results 81 to 90 of about 1,449 (134)
Spectra and fine Spectra of the upper triangular band matrix U(a;0;b) over the sequence space c0
Miskolc Mathematical Notes, 2019 The aim of this paper is to obtain the spectrum, fine spectrum, approximate point spectrum, defect spectrum and compression spectrum of the operator U.aI0Ib/D 266666664 a0 0 b0 0 0 0 0 0 0 0 a1 0 b1 0 0 0 0 0 0 0 a2 0 b2 0 0 0 0 0 0 0 a0 0 b0 0 0 0 0 0 0
N. Durna
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Local spectral theory of endomorphisms of the disk algebra
Demonstratio Mathematica, 2016 Let A(𝔻) denote the disk algebra. Every endomorphism of A(𝔻) is induced by some ϕ ∈ A(𝔻) with ‖ϕ‖ ≤ 1. In this paper, it is shown that if ϕ is not an automorphism of 𝔻 and ϕ has a fixed point in the open unit disk then the endomorphism induced by ϕ is ...
Trivedi Shailesh, Chandra Harish
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An introduction to the distorted Fourier transform
Advanced Nonlinear StudiesThis article is intended as an introduction to the distorted Fourier transform associated with a Schrödinger operator on the line or the half-line. This versatile tool has seen numerous applications in nonlinear PDE in recent years.
Ko Haram, Schlag Wilhelm
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Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2014 In this paper, using the boundary properties of the analytic functions we investigate the structure of the discrete spectrum of the boundary value problem (0.1)iy1'+q1(x)y2−λy1=ϕ1(x) −iy2'+q2(x)y1−λy2=ϕ2(x),x∈R+$$\matrix{\hfill {iy_1^\prime + q_1 \left ...
Karaman Özkan
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Spectra and fine spectra of certain lower triangular double-band matrices as operators on c0
, 2014 In this paper we determine the fine spectrum of the generalized difference operator Δa,b defined by a lower triangular double-band matrix over the sequence space c0.
S. El-Shabrawy
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A note on preservers of pseudo spectrum of matrix products
Operators and Matrices, 2019 Let M2 be the algebra of 2×2 complex matrices. For ε > 0 , complete descriptions are given of the maps of M2 leaving invariant the ε -pseudo spectrum of A ∗B , where A ∗B stands either for the Jordan semi-triple product ABA or the skew product AB∗ on ...
M. Bendaoud, A. Benyouness, M. Sarih
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Semigroup estimates and fast-slow dynamics in parabolic-hyperbolic systems
Advances in Nonlinear Analysis, 2018 We present a general procedure to describe slow dynamics in parabolic-hyperbolic systems, under suitable assumptions on the terms appearing in the equations. In particular, our strategy relies in semigroup estimates for the evolution system associated to
Strani Marta
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On quasi-∗-n-paranormal operators
, 2015 For a positive integer n , an operator T ∈ B(H) is called quasi-∗ -n -paranormal if ||T 2+nx|| 1 1+n ||Tx|| n 1+n ||T ∗Tx|| for every x∈H , which is a further generalization of hyponormal and a subclass of normaloid.
Fei Zuo
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Maps preserving the peripheral local spectrum of some product of operators
Operators and Matrices, 2019 Let H and K be two infinite-dimensional complex Hilbert spaces. Let B(H ) denote the algebra of all bounded linear operators on H . If T is an operator in B(H ) and x a vector in H then γT (x) denotes the peripheral local spectrum of T at x .
A. E. Ghazi, Rabi Marzouki
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Study of weighted elliptic composition operators on the unit ball of ℂN
Concrete OperatorsWe study the general properties, point spectrum and spectrum of a weighted composition operator Wm,φ{W}_{m,\varphi } with elliptic symbol φ\varphi on the unit ball BN{{\mathbb{B}}}_{N} of CN{{\mathbb{C}}}^{N}, and general weight m∈Hol(BN)m\in {\rm{Hol}}\
Oger Lucas
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