English
Related papers

Related papers: The spectral function of a first order system

200 papers

In this paper, we obtain asymptotic formulas for eigenvalues and eigenfunctions of the operator generated by a system of ordinary differential equations with summable coefficients and the quasiperiodic boundary conditions. Using these…

Spectral Theory · Mathematics 2007-09-21 O. A. Veliev

This seminal paper marks the beginning of our investigation into on the spectral theory based on $S$-spectrum applied to the Dirac operator on manifolds. Specifically, we examine in detail the cases of the Dirac operator $\mathcal{D}_H$ on…

Functional Analysis · Mathematics 2025-04-18 Ivan Beschastnyi , Fabrizio Colombo , Simão Andrade Lucas , Irene Sabadini

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 revisit the problem of semiclassical spectral asymptotics for a pure magnetic Schr\"odinger operator on a two-dimensional Riemannian manifold. We suppose that the minimal value $b_0$ of the intensity of the magnetic field is strictly…

Spectral Theory · Mathematics 2013-12-20 Bernard Helffer , Yuri A. Kordyukov

We perform quantitative spectral analysis of the self-adjoint Dirichlet Laplacian $\mathsf{H}$ on an unbounded, radially symmetric (generalized) parabolic layer $\mathcal{P}\subset\mathbb{R}^3$. It was known before that $\mathsf{H}$ has an…

Spectral Theory · Mathematics 2018-06-01 Pavel Exner , Vladimir Lotoreichik

We analyze the limit of the spectrum of a geometric Dirac-type operator under a collapse with bounded diameter and bounded sectional curvature. In the case of a smooth limit space B, we show that the limit of the spectrum is given by the…

Differential Geometry · Mathematics 2007-05-23 John Lott

We consider eigenvalues of the Dirichlet-to-Neumann operator for Laplacian in the domain (or manifold) with edges and establish the asymptotics of the eigenvalue counting function \begin{equation*} \mathsf{N}(\lambda)= \kappa_0\lambda^d…

Spectral Theory · Mathematics 2018-02-22 Victor Ivrii

Let $M$ be a compact boundaryless Riemannian manifold, carrying an effective and isometric action of a torus $T$, and $P_0$ an invariant elliptic classical pseudodifferential operator on $M$. In this note, we strengthen asymptotics for the…

Spectral Theory · Mathematics 2018-09-24 Pablo Ramacher

We derive the spectrum of the Dirac operator for the linear sigma-model with quarks in the large N_c approximation using renormalization group flow equations. For small eigenvalues, the Banks-Casher relation and the vanishing linear term…

High Energy Physics - Phenomenology · Physics 2009-11-07 T. Spitzenberg , K. Schwenzer , H. -J. Pirner

In this paper we examine the asymptotic structure of the pseudospectrum of the singular Sturm-Liouville operator $L=\partial_x(f\partial_x)+\partial_x$ subject to periodic boundary conditions on a symmetric interval, where the coefficient…

Spectral Theory · Mathematics 2024-06-13 Lyonell Boulton , Marco Marletta

Let $M$ be a connected, noncompact, complete Riemannian manifold, consider the operator $L=\DD +\nn V$ for some $V\in C^2(M)$ with $\exp[V]$ integrable w.r.t. the Riemannian volume element. This paper studies the existence of the spectral…

Differential Geometry · Mathematics 2016-09-07 Feng-Yu Wang

For a scalar elliptic self-adjoint operator on a compact manifold without boundary we have two-term asymptotics for the number of eigenvalues between zero and lambda when lambda tends to infinity, under an additional dynamical condition.…

Spectral Theory · Mathematics 2020-07-30 Zhirayr Avetisyan , Johannes Sjoestrand , Dmitri Vassiliev

We use the averaged variational principle introduced in a recent article on graph spectra [7] to obtain upper bounds for sums of eigenvalues of several partial differential operators of interest in geometric analysis, which are analogues of…

Metric Geometry · Mathematics 2015-12-24 Ahmad El Soufi , Evans Harrell , Said Ilias , Joachim Stubbe

We build a combinatorial invariant, called the spectral monodromy from the spectrum of a non-selfadjoint h -pseudodifferential operator with two degrees of freedom in the semi-classical limit. We treat small non-selfadjoint perturbation of…

Mathematical Physics · Physics 2014-08-05 Quang Sang Phan

In this work we prove that the eigenvalues of the $n$-dimensional massive Dirac operator $\mathscr{D}_0 + V$, $n\ge2$, perturbed by a possibly non-Hermitian potential $V$, are localized in the union of two disjoint disks of the complex…

Spectral Theory · Mathematics 2021-02-18 Piero D'Ancona , Luca Fanelli , Nico Michele Schiavone

In this paper, we consider a problem for the first order Dirac differential equations system with spectral parameter dependent in boundary condition. The asymptotic behaviors of eigenvalues, eigenfunctions and normalizing numbers of this…

Spectral Theory · Mathematics 2014-04-02 Kh. R. Mamedov , O. Akcay

This is a review of some coordinate-free calculi of pseudodifferential operators developed in the last years. As an application, we use a coordinate-free calculus to obtain new results on the behaviour of the spectral projections of a…

Analysis of PDEs · Mathematics 2011-06-21 P. Mckeag , Y. Safarov

For first order systems, we obtain an efficient bound on the exponential decay of an eigenfunction in terms of the distance between the corresponding eigenvalue and the essential spectrum. As an example, the Dirac operator is considered.

Spectral Theory · Mathematics 2007-05-23 D. R. Yafaev

In this article, we consider the Dirac operator with constant magnetic field in $\mathbb R^2$. Its spectrum consists of eigenvalues of infinite multiplicities, known as the Landau-Dirac levels. Under compactly supported perturbations, we…

Spectral Theory · Mathematics 2025-12-16 Vincent Bruneau , Pablo Miranda

We study the spectra of non-selfadjoint first-order operators on the interval with non-local point interactions, formally given by ${i\partial_x+V+k\langle \delta,\cdot\rangle}$. We give precise estimates on the location of the eigenvalues…

Spectral Theory · Mathematics 2025-02-11 Christoph Fischbacher , Danie Paraiso , Chloe Povey-Rowe , Brady Zimmerman