Results 11 to 20 of about 478 (248)
Electronic Journal of Qualitative Theory of Differential Equations, 2013 The existence and compactness of the resolvent are studied in this paper. One of the main results is the criterion of discreteness of the spectrum of a hyperbolic singular differential operator.
Mussakan Muratbekov +2 more
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Direct and inverse spectral problems for Dirac systems with nonlocal potentials [PDF]
Opuscula Mathematica, 2019 The main purposes of this paper are to study the direct and inverse spectral problems of the one-dimensional Dirac operators with nonlocal potentials. Based on informations about the spectrum of the operator, we find the potential and recover the form of
Kamila Dębowska, Leonid P. Nizhnik
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Spectrum of a family of operators [PDF]
Surveys in Mathematics and its Applications, 2011 Having as start point the classic definitions of resolvent set and spectrum of a linear bounded operator on a Banach space, we introduce the resolvent set and spectrum of a family of linear bounded operators on a Banach space.
Simona Macovei
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Properties and for Bounded Linear Operators
Journal of Mathematics, 2013 We shall consider properties which are related to Weyl type theorem for bounded linear operators , defined on a complex Banach space . These properties, that we call property , means that the set of all poles of the resolvent of of finite rank in the ...
M. H. M. Rashid
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Eigenvalue estimates for operators with finitely many negative squares [PDF]
Opuscula Mathematica, 2016 Let \(A\) and \(B\) be selfadjoint operators in a Krein space. Assume that the resolvent difference of \(A\) and \(B\) is of rank one and that the spectrum of \(A\) consists in some interval \(I\subset\mathbb{R}\) of isolated eigenvalues only.
Jussi Behrndt +2 more
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Resolvent for Non-Self-Adjoint Differential Operator with Block-Triangular Operator Potential
Abstract and Applied Analysis, 2016 A resolvent for a non-self-adjoint differential operator with a block-triangular operator potential, increasing at infinity, is constructed. Sufficient conditions under which the spectrum is real and discrete are obtained.
Aleksandr Mikhailovich Kholkin
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Localizable spectrum and bounded local resolvent functions [PDF]
Archiv der Mathematik, 2008 Given a Banach space operator with interior points in the localizable spectrum and without non-trivial divisible subspaces, this article centers around the construction of an infinite-dimensional linear subspace of vectors at which the local resolvent function of the operator is bounded and even admits a continuous extension to the closure of its ...
Müller, V. (Vladimír), Neumann, M.M.
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Rotationally resolved electronic spectrum of propadienylidene
Journal of Molecular Spectroscopy, 2005 Abstract The rotationally resolved electronic spectrum of a vibrational band in the A ˜ 1 A 2 – X ˜ 1 A 1 transition of the cumulene carbon chain C 3 H 2 was measured in the 625 nm region in a supersonic discharge using cw cavity ring down spectroscopy. The rotational structure was analysed using
Birza, Petre +4 more
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International Journal of Mathematics and Mathematical Sciences, 1995 A singular non-self-adjoint boundary value problem is considered. This problem has a discontinuous coefficient with a spectral parameter in the boundary condition. Some solutions of the eigenvalue equation are given.
A. A. Darwish
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Open Mathematics, 2023 In this article, we focus on the scattering analysis of Sturm-Liouville type singular operator including an impulsive condition and turning point. In the classical literature, there are plenty of papers considering the positive values of the weight ...
Çoşkun Nimet, Görgülü Merve
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