Results 51 to 60 of about 142 (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
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On the completely indeterminate case for block Jacobi matrices
Concrete Operators, 2017 We consider the infinite Jacobi block matrices in the completely indeterminate case, i. e. such that the deficiency indices of the corresponding Jacobi operators are maximal.
Osipov Andrey
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Fixed Point in Non-Archimedeant T -Banach Spaces [PDF]
In this paper, we introduce the concept of T -normed space in a non-Archimedean space, which is called a non-Archimedean T -normed space and give some properties.
TALLAB , ABDELHAMID +2 more
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Finite-dimensional approximations of the resolvent of an infinite band matrix and continued fractions [PDF]
, 1999 19 pages, no figures.-- MSC1991 codes: Primary 47B99, 47A10, 40A15; Secondary 30B70.-- Originally published in Russian language by the Russian Academy of Mathematics in: Matematicheskii Sbornik 190(4): 23–42 (1999).MR#: MR1702505 (2000e:47052)Zbl#: Zbl ...
López Lagomasino, Guillermo +3 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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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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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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The Resolvent of Impulsive Singular Hahn–Sturm–Liouville Operators
Annales Mathematicae SilesianaeIn this study, the resolvent of the impulsive singular Hahn–Sturm– Liouville operator is considered. An integral representation for the resolvent of this operator is obtained.
Allahverdiev Bilender P. +2 more
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