Results 41 to 50 of about 10,340 (200)
Electronic Journal of Qualitative Theory of Differential Equations, 2014 In this article we obtain the eigenfunction expansions of a quadratic pencil of Sturm-Liouville operators with periodic coefficients. The important point to note here is the given potential is a first order generalized function.
Manaf Manafov, Abdullah Kablan
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Inverse spectral problems for energy-dependent Sturm-Liouville equations
, 2012 We study the inverse spectral problem of reconstructing energy-dependent Sturm-Liouville equations from their Dirichlet spectra and sequences of the norming constants.
Ablowitz M J +42 more
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Embedded eigenvalues of Sturm Liouville operators [PDF]
Communications in Mathematical Physics, 1991 The behaviour of embedded eigenvalues for Sturm-Liouville problems in \([0,\infty)\) under local perturbations is studied. If the spectral function has a strictly positive derivative then the embedded eigenvalues either disappear or remain fixed. In this case local perturbations cannot add eigenvalues in the continuous spectrum.
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Scattering matrices and Weyl functions [PDF]
, 2006 For a scattering system $\{A_\Theta,A_0\}$ consisting of selfadjoint extensions $A_\Theta$ and $A_0$ of a symmetric operator $A$ with finite deficiency indices, the scattering matrix $\{S_\gT(\gl)\}$ and a spectral shift function $\xi_\Theta$ are ...
Behrndt, Jussi +2 more
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Boundary Value Problems, 2018 We give a new approach for the estimations of the eigenvalues of non-self-adjoint Sturm–Liouville operators with periodic and antiperiodic boundary conditions. Moreover, we give error estimations, and finally we present some numerical examples.
Cemile Nur
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Spectral properties of singular Sturm-Liouville operators with indefinite weight sgn x [PDF]
, 2007 We consider a singular Sturm-Liouville expression with the indefinite weight sgn x. To this expression there is naturally a self-adjoint operator in some Krein space associated.
Karabash, I., Trunk, C.
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Effect of Field Line Torsion on the Polarization of ULF Waves
Journal of Geophysical Research: Space Physics, Volume 131, Issue 5, May 2026.Abstract In this paper we suggest a simple modification of the dipole magnetic field which introduces field‐aligned currents and torsion to the field lines. The resulting field lines are not contained in the meridional planes and have resemblance to the geomagnetic field lines in the dawn and dusk flanks of the magnetosphere. We analyze polarization of
K. Kabin, A. W. Degeling, R. Rankin
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Determinants of Regular Singular Sturm ‐ Liouville Operators [PDF]
Mathematische Nachrichten, 1998 AbstractWe consider a regular singular Sturm‐Liouville operator equation image on the line segment (0,1]. We impose certain boundary conditions such that we obtain a semi‐bounded self‐adjoint operator. It is known (cf. Theorem 1.1 below) that the ζ‐function of this operator equation image has a meromorphic continuation to the whole complex plane with 0
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Maximally dissipative and self‐adjoint extensions of K$K$‐invariant operators
Bulletin of the London Mathematical Society, Volume 58, Issue 5, May 2026.Abstract We introduce the notion of K$K$‐invariant operators, S$S$, in a Hilbert space, with respect to a bounded and boundedly invertible operator K$K$ defined via K∗SK=S$K^*SK=S$. Conditions such that self‐adjoint and maximally dissipative extensions of K$K$‐invariant symmetric operators are also K$K$‐invariant are investigated.
Christoph Fischbacher +2 more
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Analytic investigation of rotating holographic superconductors
European Physical Journal C: Particles and Fields, 2019 In this paper we have investigated, in the probe limit, s-wave holographic superconductors in rotating $$AdS_{3+1}$$ AdS3+1 spacetime using the matching method as well as the Stürm–Liouville eigenvalue approach.
Ankur Srivastav, Sunandan Gangopadhyay
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