Results 61 to 70 of about 142 (138)
Properties of absolute-∗-k-paranormal operators and contractions for ∗-A(k) operators [PDF]
, 2019 First, we see if T is absolute-∗-k-paranormal for k ≥ 1, then T is a normaloid operator. We also see some properties of absolute-∗-k-paranormal operator and ∗-A(k) operator.
BRAHA, Naim L., HOXHA, Ilmi, TATO, Agron
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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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On the regularized trace of a fourth order regular differential equation, Int
, 2020 We shall obtain a formula for the regularized trace of a fourth order regular differential equation. Mathematics Subject Classification: 34L05, 47A10 Keywords: Asymptotics of eigenvalues and eigenfunctions, unitary matrix, regularized trace. STATEMENT OF
Azad Bayramov +4 more
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Surjective isometries of C*-algebras: complex spectrum and periodicity
Concrete OperatorsIn this paper, we are interested in studying surjective isometries of C*-algebras with an emphasis on their complex spectrum. We do not require the isometries to be linear nor the C*-algebras to be unital.
Bénéteau Catherine +6 more
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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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© Hindawi Publishing Corp. ON THE LARGEST ANALYTIC SET FOR CYCLIC OPERATORS
, 2002 We describe the set of analytic bounded point evaluations for an arbitrary cyclic bounded linear operator T on a Hilbert space ; some related consequences are discussed.
A. Bourhim
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Radius preserving (semi) regularities in banach algebras
, 2019 In this note we investigate regularities (semiregularities) R and S in a Banach algebra A satisfying S ⊂ R and the corresponding spectra σS and σR satisfyingsup{|λ| : λ ∈ σ R(a)g = sup{|λ| : ∈ 2 σ S(a)}for all a ∈ A.Mathematics Subject Classification ...
Raubenheimer, H, Swartz, A
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On Inverse Spectral Theory for Self-Adjoint Extensions: Mixed Types of Spectra [PDF]
, 1998 LetHbe a symmetric operator in a separable Hilbert space H. Suppose thatHhas some gapJ. We shall investigate the question about what spectral properties the self-adjoint extensions ofHcan have inside the gapJand provide methods on how to construct self ...
Albeverio, Sergio +2 more
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Characterization and stability of essential pseudospectra by measure of polynomially inessential operators [PDF]
In this article, we investigate the essential pseudospectra through the framework of polynomially inessential operators, which extends the class of polynomially strictly singular operators and provides a broader setting for Fredholm-type ...
ELGABEUR, Bilel
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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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