Results 41 to 50 of about 5,416,832 (202)
Stable factorization of the Calderón problem via the Born approximation
Journal of the London Mathematical Society, Volume 113, Issue 6, June 2026.Abstract In this article, we prove the existence of the Born approximation in the context of the radial Calderón problem for Schrödinger operators. The Born approximation naturally appears as the linear component of a factorization of the Calderón problem; we show that the nonlinear part, obtaining the potential from the Born approximation, enjoys ...
Thierry Daudé +3 more
wiley +1 more source
Inverse spectral problems for Sturm–Liouville operators with partial information [PDF]
, 2014 In this paper, we study the inverse spectral problems for Sturm–Liouville operators with Robin boundary conditions and show that if the potential q on the interval [0,α] for some α∈[0,1) is given a priori, then the potential q on the whole interval [0,1]
Wang, Yu-Ping; Shieh, Chung-Tsun; Ma, Yan-Ting +1 more
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A metric Sturm–Liouville theory in two dimensions [PDF]
Calculus of Variations and Partial Differential Equations, 2019 A central result of Sturm-Liouville theory (also called the Sturm-Hurwitz Theorem) states that if $ϕ_k$ is a sequence of eigenfunctions of a second order differential operator on the interval $I \subset \mathbb{R}$, then any linear combination satisfies a uniform bound on the roots $$ \# \left\{x \in I:\sum_{k \geq n}{ a_k ϕ_k(x)} = 0 \right\} \geq n-1.
openaire +3 more sources
Internal Wave Characteristics in the Andaman Sea: New Insights From SWOT Observations
Geophysical Research Letters, Volume 53, Issue 10, 28 May 2026.Abstract High‐resolution, repeat‐pass Sea Surface Height Anomaly (SSHA) observations from the Surface Water and Ocean Topography (SWOT) satellite are used to investigate Internal Solitary Waves (ISW) in the Andaman Sea over a one‐year period starting in July 2023. SWOT captured surface signatures of high‐amplitude ISW, with SSHA exceeding 20 cm.
Anup Kumar Mandal +7 more
wiley +1 more source
Special functions and generalized Sturm-Liouville problems
, 2020 This book discusses theoretical and applied aspects of Sturm-Liouville theory and its generalization. It introduces and classifies generalized Sturm-Liouville problems in three different spaces: continuous, discrete, and q-discrete spaces, focusing on ...
Masjed-Jamei, Mohammad
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Қарағанды университетінің хабаршысы. Математика сериясыThis paper is devoted to a new type of boundary-value problems for Sturm-Liouville equations defined on three disjoint intervals (−π,−π+d),(−π+d,π−d) and (π−d,π) together with eigenparameter dependent boundary conditions and with additional transmission
H. Olǧar, F. Muhtarov, O. Mukhtarov
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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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Some Further Insight into the Sturm–Liouville Theory
MathematicsSome classical texts on the Sturm–Liouville equation (p(x)y′)′−q(x)y+λρ(x)y=0 are revised to highlight further properties of its solutions. Often, in the treatment of the ensuing integral equations, ρ=const is assumed (and, further, ρ=1).
Salvatore De Gregorio +2 more
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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
wiley +1 more source
Continuations of Hermitian indefinite functions and corresponding canonical systems : an example [PDF]
, 2004 M. G. Krein established a close connection between the continuation problem of positive definite functions from a finite interval to the real axis and the inverse spectral problem for differential operators.
Langer, M. +5 more
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