Results 51 to 60 of about 141 (138)
Joint numerical ranges: recent advances and applications minicourse by V. Müller and Yu. Tomilov
Concrete Operators, 2020 We present a survey of some recent results concerning joint numerical ranges of n-tuples of Hilbert space operators, accompanied with several new observations and remarks.
Müller V., Tomilov Yu.
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Almost Jordan homomorphisms on Fréchet algebras
, 2021 In this paper we study the notation of almost Jordan homomorphism between Fréchet algebras. We show that if (A; (pn)) is a Fréchet algebra and T : A → ℂ is a almost Jordan homomorphism, then either T is homomorphism, or it is continuous.
Zivari-Kazempour, A. +2 more
core
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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Spectral properties of generalized eigenparameter dependent discrete Sturm-Liouville type equation
, 2017 Let L denote the non-selfadjoint difference operator of second order with boundary condition generated in ℓ2 (ℕ) byan-1yn-1 + bnyn + anyn+1 = λyn ; n ∈ ℕ; (0.1)pΣk=0 (y1γk + y0βk) λk = 0; (0.2)where {an} n∈ℕ and {bn} n∈ℕ are complex ...
Mohapatra, R. N. +4 more
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Ultrametric Fredholm operators and approximate pseudospectrum [PDF]
Arab Journal of Mathematical SciencesPurposeThe paper deals with ultrametric bounded Fredholm operators and approximate pseudospectra of closed and densely defined (resp. bounded) linear operators on ultrametric Banach spaces.Design/methodology/approachThe author used the notions of ...
Jawad Ettayb
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The invertibility of 2x2 operator matrices [PDF]
, 2014 In this paper the properties of right invertible row operators, i.e., of 1x2 surjective operator matrices are studied. This investigation is based on a specific space decomposition.
Trunk, Carsten +3 more
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Compact Jacobi matrices: from Stieltjes to Krein and M(a,b) [PDF]
, 1996 . --- In a note at the end of his paper Recherches sur les fractions continues, Stieltjes gave a necessary and sufficient condition when a continued fraction is represented by a meromorphic function. This result is related to the study of compact Jacobi
Walter Van Assche, Van Assche, Walter
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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
core
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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