Results 41 to 50 of about 29,873 (226)
Density-potential mappings in quantum dynamics
, 2012 In a recent letter [Europhys. Lett. 95, 13001 (2011)] the question of whether the density of a time-dependent quantum system determines its external potential was reformulated as a fixed point problem.
A. Bielecki +15 more
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A matrix method for fractional Sturm-Liouville problems on bounded domain [PDF]
, 2017 A matrix method for the solution of direct fractional Sturm-Liouville problems on bounded domain is proposed where the fractional derivative is defined in the Riesz sense.
Ghelardoni, Paolo, Magherini, Cecilia
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Scattering theory for difference equations with operator coefficients
Journal of the London Mathematical Society, Volume 113, Issue 3, March 2026.Abstract We investigate a class of second‐order difference equations featuring operator‐valued coefficients with the aim of approaching problems of stationary scattering theory. We focus on various compact perturbations of the discrete Laplacian given in a Hilbert space of bi‐infinite square‐summable sequences with entries from a fixed Hilbert space ...
David Sher +3 more
wiley +1 more source
Wasit Journal for Pure Sciences: In this study, we provide an overview of the Sturm-Liouville operator’s spectral theory on a finite interval. Also, we study the main spectral characteristics for the second-order differential operator, and we show that the eigenvalues and ...
khelan hussien
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Spectral Parameter Power Series Representation for Regular Solutions of the Radial Dirac System
Mathematical Methods in the Applied Sciences, Volume 49, Issue 3, Page 2098-2113, February 2026.ABSTRACT A spectral parameter power series (SPPS) representation for the regular solution of the radial Dirac system with complex coefficients is obtained, as well as a SPPS representation for the (entire) characteristic function of the corresponding spectral problem on a finite interval. Based on the SPPS representation, a numerical method for solving
Emmanuel Roque, Sergii M. Torba
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Domains of time-dependent density-potential mappings
, 2011 The key element in time-dependent density functional theory is the one-to-one correspondence between the one-particle density and the external potential. In most approaches this mapping is transformed into a certain type of Sturm-Liouville problem.
Penz, Markus, Ruggenthaler, Michael
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Maxwell Fronts in the Discrete Nonlinear Schrödinger Equations With Competing Nonlinearities
Studies in Applied Mathematics, Volume 156, Issue 2, February 2026.ABSTRACT In discrete nonlinear systems, the study of nonlinear waves has revealed intriguing phenomena in various fields such as nonlinear optics, biophysics, and condensed matter physics. Discrete nonlinear Schrödinger (DNLS) equations are often employed to model these dynamics, particularly in the context of Bose–Einstein condensates and optical ...
Farrell Theodore Adriano, Hadi Susanto
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Relative Oscillation Theory, Weighted Zeros of the Wronskian, and the Spectral Shift Function
, 2008 We develop an analog of classical oscillation theory for Sturm-Liouville operators which, rather than measuring the spectrum of one single operator, measures the difference between the spectra of two different operators. This is done by replacing zeros
A. Kneser +38 more
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Mathematical Methods in the Applied Sciences, Volume 49, Issue 2, Page 521-530, 30 January 2026.ABSTRACT This paper investigates the generalized Hyers–Ulam stability of the Laplace equation subject to Neumann boundary conditions in the upper half‐space. Traditionally, Hyers–Ulam stability problems for differential equations are analyzed by examining the system's error, particularly in relation to a forcing term.
Dongseung Kang +2 more
wiley +1 more source
Regularized Green's Function for the Inverse Square Potential
, 2002 A Green's function approach is presented for the D-dimensional inverse square potential in quantum mechanics. This approach is implemented by the introduction of hyperspherical coordinates and the use of a real-space regulator in the regularized version ...
CARLOS R. ORDÓÑEZ +5 more
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