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Related papers: Spectral properties of non-self-adjoint operators

200 papers

We study various spectral theoretic aspects of non-self-adjoint operators. Specifically, we consider a class of factorable non-self-adjoint perturbations of a given unperturbed non-self-adjoint operator and provide an in-depth study of a…

Spectral Theory · Mathematics 2020-05-06 Fritz Gesztesy , Yuri Latushkin , Marius Mitrea , Maxim Zinchenko

We study the contraction semigroups of elliptic quadratic differential operators. Elliptic quadratic differential operators are the non-selfadjoint operators defined in the Weyl quantization by complex-valued elliptic quadratic symbols. We…

Analysis of PDEs · Mathematics 2007-05-23 Karel Pravda-Starov

In this note semibounded self-adjoint extensions of symmetric operators are investigated with the help of the abstract notion of quasi boundary triples and their Weyl functions. The main purpose is to provide new sufficient conditions on…

Spectral Theory · Mathematics 2017-10-23 Jussi Behrndt , Matthias Langer , Vladimir Lotoreichik , Jonathan Rohleder

The central problem we consider is the distribution of eigenvalues of closed linear operators which are not selfadjoint, with a focus on those operators which are obtained as perturbations of selfadjoint linear operators. Two methods are…

Spectral Theory · Mathematics 2014-03-25 Michael Demuth , Marcel Hansmann , Guy Katriel

It is shown that the nonselfadjoint (and non-normal) linear ordinary differential operators of a certain class are spectral operators of scalar type in the sense of Dunford and Bade. Operators of this kind appear in physical problems such…

Spectral Theory · Mathematics 2026-03-27 Victor Laliena

We study spectral asymptotics for a large class of differential operators on an open subset of $\R^d$ with finite volume. This class includes the Dirichlet Laplacian, the fractional Laplacian, and also fractional differential operators with…

Spectral Theory · Mathematics 2015-06-17 Leander Geisinger

In this paper we give an estimate on the asymptotic behavior of eigenvalues of discretized elliptic boundary values problems. We first prove a simple min-max principle for selfadjoint operators on a Hilbert space. Then we show two sided…

Numerical Analysis · Mathematics 2019-11-01 Jinchao Xu , Hongxuan Zhang , Ludmil Zikatanov

We discuss properties of $L^2$-eigenfunctions of Schr\"odinger operators and elliptic partial differential operators. The focus is set on unique continuation principles and equidistribution properties. We review recent results and announce…

Analysis of PDEs · Mathematics 2016-01-08 Denis Borisov , Martin Tautenhahn , Ivan Veselic

We give a spectral description of the semi-classical Schrodinger operator with a piecewise linear, complex valued potential. Moreover, using these results, we show how an arbitrarily small bounded perturbation of a non-self-adjoint operator…

Spectral Theory · Mathematics 2007-05-23 P. Redparth

Spectra of the second derivative operators corresponding to the special PT-symmetric point interactions are studied. The results are partly the completion of those obtained in [1]. The particular PT-symmetric point interactions causing…

Mathematical Physics · Physics 2009-06-02 Petr Siegl

The paper aims to study the spectral properties of elliptic operators with highly inhomogeneous coefficients and related issues concerning wave propagation in high-contrast media. A unified approach to solving problems in bounded domains…

Analysis of PDEs · Mathematics 2025-12-19 Yuri A. Godin , Leonid Koralov , Boris Vainberg

The spectral problem for self-adjoint extensions is studied using the machinery of boundary triplets. For a class of symmetric operators having Weyl functions of a special type we calculate explicitly the spectral projections in the form of…

Functional Analysis · Mathematics 2013-09-17 Konstantin Pankrashkin

We study the spectrum of a periodic self-adjoint operator on the axis perturbed by a small localized nonself-adjoint operator. It is shown that the continuous spectrum is independent of the perturbation, the residual spectrum is empty, and…

Spectral Theory · Mathematics 2007-05-23 D. Borisov , R. Gadyl'shin

The inverse problem of spectral analysis for the non-self-adjoint matrix Sturm-Liouville operator on a finite interval is investigated. We study properties of the spectral characteristics for the considered operator, and provide necessary…

Spectral Theory · Mathematics 2014-07-15 Natalia Bondarenko

We consider a non-selfadjoint $h$-differential model operator $P_h$ in the semiclassical limit ($h\rightarrow 0$) subject to small random perturbations. Furthermore, we let the coupling constant $\delta$ be $\exp\{-\frac{1}{Ch}\}\leq \delta…

Spectral Theory · Mathematics 2015-12-22 Martin Vogel

This article is devoted to the spectral analysis of the electro-magnetic Schr\"odinger operator on the Euclidean plane. In the semiclassical limit, we derive a pseudo-differential effective operator that allows us to describe the spectrum…

Spectral Theory · Mathematics 2022-01-26 Léo Morin , Nicolas Raymond , San Vu Ngoc

We investigate the spectral asymptotic behavior of operator-valued classical pseudo-differential operators ($\Psi$DOs) for negative order with symbols taking values in a semifinite von Neumann algebran $\mathcal{M}$ equipped with a normal…

Operator Algebras · Mathematics 2026-05-20 Edward McDonald , Xiao Xiong , Xinyu Zhang

In this paper we construct the spectral expansion for the non-self-adjoint differential operators generated in the space of vektor functions by the ordinary differential expression of arbitrary order with the periodic matrix coefficients by…

Spectral Theory · Mathematics 2021-12-24 O. A. Veliev

We consider self-adjoint extensions of differential operators of the type $ (-\frac{d^2}{dr^2} + \frac{l(l+1)}{r^2})^3 $ on the real semi-axis for l=1,2 with two kinds of boundary conditions: first that nullify the value of a function and…

Spectral Theory · Mathematics 2014-10-13 T. A. Bolokhov

We consider a class of one-dimensional nonselfadjoint semiclassical pseudo-differential operators, subject to small random perturbations, and study the statistical properties of their (discrete) spectra, in the semiclassical limit $h\to 0$.…

Spectral Theory · Mathematics 2022-01-19 Stéphane Nonnenmacher , Martin Vogel