Results 21 to 30 of about 13,845 (157)

Spectral partitions for Sturm-Liouville problems

, 2018
We look for best partitions of the unit interval that minimize certain functionals defined in terms of the eigenvalues of Sturm-Liouville problems. Via \Gamma-convergence theory, we study the asymptotic distribution of the minimizers as the number of ...
Tilli, Paolo, Zucco, Davide
core   +1 more source

Application of approximation theory by nonlinear manifolds in Sturm-Liouville inverse problems

, 2006
We give here some negative results in Sturm-Liouville inverse theory, meaning that we cannot approach any of the potentials with $m+1$ integrable derivatives on $\mathbb{R}^+$ by an $\omega$-parametric analytic family better than order of $(\omega\ln ...
Amadeo Irigoyen, Chadan K, Gelfand I M, Henkin G M, Irigoyen A, Lax P D, Lax P D, Lax P D, Levitan B M, Markushevich V M, Reed M, Vitushkin A G   +11 more
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Fractal Sturm–Liouville Theory

Fractal and Fractional
This paper provides a short summary of fractal calculus and its application to generalized Sturm–Liouville theory. It presents both the fractal homogeneous and non-homogeneous Sturm–Liouville problems and explores the theory’s applications in optics.
Alireza Khalili Golmankhaneh, Zoran Vidović, Hüseyin Tuna, Bilender P. Allahverdiev   +3 more
doaj   +1 more source

Existence of solutions for subquadratic convex or $B$-concave operator equations and applications to second order Hamiltonian systems

Electronic Journal of Qualitative Theory of Differential Equations, 2020
This paper investigates solutions for subquadratic convex or $B$-concave operator equations. First, some existence results are obtained by the index theory and the critical point theory.
Mingliang Song
doaj   +1 more source

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, A. Zettl, B. Simon, B. Simon, D.R. Yafaev, F. Gesztesy, F. Gesztesy, F. Gesztesy, F.S. Rofe-Beketov, F.S. Rofe-Beketov, F.S. Rofe-Beketov, F.S. Rofe-Beketov, G. Stolz, G. Teschl, G. Teschl, G. Teschl, G. Teschl, Gerald Teschl, H. Krüger, Helge Krüger, I. Gohberg, J. Weidmann, J. Weidmann, J. Weidmann, J.C.F. Sturm, K.M. Schmidt, K.M. Schmidt, K.M. Schmidt, M. Reed, M.G. Krein, M.S.P. Eastham, M.Sh. Birman, P. Hartman, P. Hartman, P. Hartman, S.V. Khryashchev, T. Kato, W. Leighton, W. Walter   +38 more
core   +8 more sources

The Solutions of Sturm-Liouville Boundary-Value Problem for Fourth-Order Impulsive Differential Equation via Variational Methods

Abstract and Applied Analysis, 2014
The Sturm-Liouville boundary-value problem for fourth-order impulsive differential equations is studied. The existence results for one solution and multiple solutions are obtained.
Yu Tian, Dongpo Sun
doaj   +1 more source

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, A. L. Fetter, A. Zettl, C. A. Ullrich, D. H. Griffel, E. Engel, K. J. H. Giesbertz, L. C. Evans, M. Bonitz, M. Penz, M. Ruggenthaler, Ph. Blanchard, R. M. Dreizler, R. van Leeuwen, W. A. Light, W. Walter   +15 more
core   +1 more source

An Extension of The First Eigen-type Ambarzumyan theorem

, 2019
An extension of the first eigenvalue-type Ambarzumyan's theorem are provided for the arbitrary self-adjoint Sturm-Liouville differential operators.
Kıraç, Alp Arslan
core   +1 more source

Study the properties of spectral characteristics and eigenfunctions for Sturm-Liouville boundary value problems

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
doaj   +1 more source

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, Bart Rosenzweig, Jonathan Stanfill   +2 more
wiley   +1 more source