Results 21 to 30 of about 499 (268)
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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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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Comptes Rendus. Mathématique, 2022 In this paper we perform the analysis of the spectrum of a degenerate operator $A_\varepsilon $ corresponding to the stationary heat equation in a $\varepsilon $-periodic composite medium having two components with high contrast diffusivity.
Sili, Ali
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Advances in Mathematical Physics, 2014 A model describing a truncated operator H (truncated with respect to the number of particles) and acting in the direct sum of zero-, one-, and two-particle subspaces of fermionic Fock space FaL2T3 over L2(T3) is investigated.
Zahriddin Muminov +2 more
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Қарағанды университетінің хабаршысы. Математика сериясыIn the article the spectrum and resolvent of the so-called multichannel systems with nonzero internal energies were investigated. The spectrum and resolvent of multichannel Sturm-Liouville systems with non-zero internal energies mi2 and general boundary
A.A. Valiyev +2 more
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On the Spectrum of a Morphism of Quotient Hilbert Spaces [PDF]
Surveys in Mathematics and its Applications, 2006 In this paper we define the notion of spectrum for a morphism of quotient Hilbert spaces. The definition is the same with the one given by L.Waelbroeck but the proofs that the spectrum is a compact and nonempty set are different.
Sorin Nadaban
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Probing multiple-frequency atom-photon interactions with ultracold atoms
New Journal of Physics, 2019 We dress atoms with multiple-radiofrequency (RF) fields and investigate the spectrum of transitions driven by an additional probe field. A complete theoretical description of this rich spectrum is presented, in which we find allowed transitions and ...
K Luksch +6 more
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Pseudo-hermitian random matrix models: General formalism
Nuclear Physics B, 2022 Pseudo-hermitian matrices are matrices hermitian with respect to an indefinite metric. They can be thought of as the truncation of pseudo-hermitian operators, defined over some Krein space, together with the associated metric, to a finite dimensional ...
Joshua Feinberg, Roman Riser
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G-Convergence of Dirac Operators
Journal of Function Spaces and Applications, 2012 We consider the linear Dirac operator with a (−1)-homogeneous locally periodic potential that varies with respect to a small parameter. Using the notation of G-convergence for positive self-adjoint operators in Hilbert spaces we prove G-compactness in ...
Hasan Almanasreh, Nils Svanstedt
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