Results 21 to 30 of about 1,194 (210)
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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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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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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Schrödinger operators with δ and δ′-potentials supported on hypersurfaces
, 2013 Self-adjoint Schrödinger operators with δ and δ′-potentials supported on a smooth compact hypersurface are defined explicitly via boundary conditions.
Lotoreichik, Vladimir +2 more
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Phase-resolved spectrum of the Crab pulsar from NICER [PDF]
Astronomy & Astrophysics, 2021 Context. Studies of the high-energy emission regions of rotation-powered pulsars are typically based on folded light curves (FLCs) and phase-resolved spectra (PRS). Aims. This work uses the NICER observatory to obtain the highest resolution FLC and PRS of the Crab pulsar at soft X-ray energies. Methods.
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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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Time-resolved optical measurements with spread spectrum excitation [PDF]
Optics Letters, 2002 We propose a novel method for measuring time-dependent optical quantities. A train of excitation pulses modulated by a pseudorandom bit sequence is used as the light source, and a cross-correlation scheme is used to retrieve the impulse response. Simulation results of the temporal point-spread function of a diffusive wave are provided, as well as ...
Nan Guang, Chen, Quing, Zhu
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Lee model and its resolvent analysis
, 2023 We revisit the relativistic (2+1)-dimensional Lee model on flat space in light-front coordinates and on a space-time with a spatial section given by a compact manifold, in the usual canonical formalism.
Jagvaral, Yesukhei +2 more
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Browder S-resolvent equation in quaternionic setting
, 2023 This paper is devoted to the study of the S-eigenvalue of finite type of a bounded right quaternionic linear operator acting in a right quaternionic Hilbert space. The study is based on the different properties of the Riesz projection associated with the
Baloudi, H., Zmouli, H., Jeribi, A.
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