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Related papers: Spectral asymptotics for canonical systems

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In this paper the asymptotic distributions are exactly solved for linearly independent solutions considering problems of the second order and for the coefficients of asymptotic destribution the recurent formulas are obtained. Further, using…

Mathematical Physics · Physics 2007-05-23 Yu. A. Mamedov , H. I. Ahmadov

We study one-parameter families of pseudodifferential operators whose Weyl symbols are obtained by dilation and a smooth deformation of a symbol in a weighted Sj\"ostrand class. We show that their spectral edges are Lipschitz continuous…

Functional Analysis · Mathematics 2023-03-24 Karlheinz Gröchenig , José Luis Romero , Michael Speckbacher

We investigate the singular Weyl-Titchmarsh m-function of perturbed spherical Schroedinger operators (also known as Bessel operators) under the assumption that the perturbation $q(x)$ satisfies $x q(x) \in L^1(0,1)$. We show existence plus…

Spectral Theory · Mathematics 2011-03-01 Aleksey Kostenko , Gerald Teschl

We present a treatment of many-body Fermionic systems that facilitates an expression of the well-known quantities in a series expansion of the Planck's constant. The ensuing semiclassical result contains to a leading order of the response…

Condensed Matter · Physics 2009-10-28 Pierre Gaspard , Sudhir R. Jain

For non-critical almost Mathieu operators with Diophantine frequency, we establish exponential asymptotics on the size of spectral gaps, and show that the spectrum is homogeneous. We also prove the homogeneity of the spectrum for…

Dynamical Systems · Mathematics 2017-12-14 Martin Leguil , Jiangong You , Zhiyan Zhao , Qi Zhou

Dynamical canonical systems and their connections with the classical (spectral) canonical systems are considered. We construct B\"acklund-Darboux transformation and explicit solutions of the dynamical canonical systems. We study also those…

Dynamical Systems · Mathematics 2018-03-20 Alexander Sakhnovich

We study spectral asymptotics for small non-selfadjoint perturbations of selfadjoint $h$-pseudodifferential operators in dimension 2, assuming that the classical flow of the unperturbed part possesses several invariant Lagrangian tori…

Spectral Theory · Mathematics 2007-05-23 Michael Hitrik , Johannes Sjoestrand , San Vu Ngoc

We extend the Euler-Bernoulli beam problem, formulated as a matrix string equation with a matrix-valued density, to a setting where the density takes values in a Clifford algebra, and we analyze its isospectral deformations. For discrete…

Exactly Solvable and Integrable Systems · Physics 2025-09-19 Richard Beals , Jacek Szmigielski

The Weyl-Wigner representations for canonical thermal equilibrium quantum states are obtained for the whole class of quadratic Hamiltonians through a Wick rotation of the Weyl-Wigner symbols of Heisenberg and metaplectic operators. The…

Quantum Physics · Physics 2021-01-13 F. Nicacio

The aim of this paper is to show that, in the limit circle case, the defect index of a symmetric relation induced by canonical systems, is constant on C. This provides an alternative proof of the De Branges theorem that the canonical…

Spectral Theory · Mathematics 2014-04-11 Keshav Raj Acharya

We study orthogonal polynomials with periodically modulated Jacobi parameters in the case when $0$ lies on the soft edge of the spectrum of the corresponding periodic Jacobi matrix. We determine when the orthogonality measure is absolutely…

Spectral Theory · Mathematics 2020-12-16 Grzegorz Świderski , Bartosz Trojan

We discuss direct and inverse spectral theory of self-adjoint Sturm-Liouville relations with separated boundary conditions in the left-definite setting. In particular, we develop singular Weyl-Titchmarsh theory for these relations.…

Spectral Theory · Mathematics 2012-05-28 Jonathan Eckhardt

A high-frequency asymptotics of the symbol of the Dirichlet-to-Neumann map, treated as a periodic pseudodifferential operator, in 2D diffraction problems is discussed. Numerical results support a conjecture on a universal limit shape of the…

Computational Physics · Physics 2007-05-23 Margo Kondratieva , Sergey Sadov

We consider 2- and 3-dimensional Schr\"odinger or generalized Schr\"odinger-Pauli operators with the non-degenerating magnetic field in the open domain under certain non-degeneracy assumptions we derive pointwise spectral asymptotics. We…

Spectral Theory · Mathematics 2010-12-08 Victor Ivrii

It has been recently conjectured that the spectral determinants of operators associated to mirror curves can be expressed in terms of a generalization of theta functions, called quantum theta functions. In this paper we study the symplectic…

High Energy Physics - Theory · Physics 2016-12-21 Alba Grassi

We investigate the strong asymptotics of Heine-Stieltjes polynomials - polynomial solutions of a second order differential equations with complex polynomial coefficients. The solution is given in terms of critical measures (saddle points of…

Classical Analysis and ODEs · Mathematics 2009-03-17 A. Martinez-Finkelshtein , E. A. Rakhmanov

We show that the new technique of terahertz 2D coherent spectroscopy is capable of giving qualitatively new information about fractionalized spin systems. For the prototypical example of the transverse field Ising chain, we demonstrate…

Strongly Correlated Electrons · Physics 2021-12-15 Yuan Wan , N. P. Armitage

In three-dimensional case, we consider two classical operators: Schrodinger operator and an operator in the divergence form. For slowly-decaying oscillating potentials, we establish spatial asymptotics of the Green's function. The main term…

Analysis of PDEs · Mathematics 2018-12-20 Sergey A. Denisov

The Staruszkiewicz quantum model of the long-range structure in electrodynamics is reviewed in the form of a Weyl algebra. This is followed by a personal view on the asymptotic structure of quantum electrodynamics.

High Energy Physics - Theory · Physics 2007-05-23 Andrzej Herdegen

The transmission problem is a system of two second-order elliptic equations of two unknowns equipped with the Cauchy data on the boundary. After four decades of research motivated by scattering theory, the spectral properties of this…

Analysis of PDEs · Mathematics 2020-08-20 Hoai-Minh Nguyen , Quoc-Hung Nguyen