English
Related papers

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

200 papers

Several recent papers have focused their attention in proving the correct analogue to the Lieb-Thirring inequalities for non self-adjoint operators and in finding bounds on the distribution of their eigenvalues in the complex plane. This…

Spectral Theory · Mathematics 2019-04-19 Lucrezia Cossetti

Criteria are formulated both for the existence and for the non-existence of complex eigenvalues for a class of non self-adjoint operators in Hilbert space invarariant under a particular discrete symmetry. Applications to the PT-symmetric…

Mathematical Physics · Physics 2009-11-10 Emanuela Caliceti , Sandro Graffi , Johannes Sjoestrand

The behaviour of the spectral edges (embedded eigenvalues and resonances) is discussed at the two ends of the continuous spectrum of non-local discrete Schr\"odinger operators with a $\delta$-potential. These operators arise by replacing…

Mathematical Physics · Physics 2013-09-20 Fumio Hiroshima , József Lőrinczi

We investigate the effect of non-symmetric relatively bounded perturbations on the spectrum of self-adjoint operators. In particular, we establish stability theorems for one or infinitely many spectral gaps along with corresponding…

Spectral Theory · Mathematics 2016-04-04 Jean-Claude Cuenin , Christiane Tretter

In this paper we consider the Bloch eigenvalues and spectrum of the non-self-adjoint differential operator L generated by the differential expression of odd order n with the periodic PT-symmetric coefficients, where n>1. We study the…

Spectral Theory · Mathematics 2023-07-27 O. A. Veliev

In this work, we investigate the spectral problem $Au = {\lambda}u$ where $A$ is a fractional elliptic operator involving left- and right-sided Riemann-Liouville derivatives. These operators are nonlocal and nonsymmetric, however, share…

Analysis of PDEs · Mathematics 2022-12-23 Quanling Deng , Yulong Li

We study the spectral convergence of compact, self-adjoint operators on a separable Hilbert space under operator norm perturbations, and derive asymptotic expansions for their eigenvalues and eigenprojections. Our analysis focuses on…

Statistics Theory · Mathematics 2026-02-10 Eunseong Bae , Wolfgang Polonik

This is the second in a series of works devoted to small non-selfadjoint perturbations of selfadjoint semiclassical pseudodifferential operators in dimension 2. As in our previous work, we consider the case when the classical flow of the…

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

We consider differential operators defined as Friedrichs extensions of quadratic forms with non-smooth coefficients. We prove a two term optimal asymptotic for the Riesz means of these operators and thereby also reprove an optimal Weyl law…

Spectral Theory · Mathematics 2022-09-15 Søren Mikkelsen

We define Dirac operators on $\mathbb{S}^3$ (and $\mathbb{R}^3$) with magnetic fields supported on smooth, oriented links and prove self-adjointness of certain (natural) extensions. We then analyze their spectral properties and show, among…

Mathematical Physics · Physics 2018-02-21 Fabian Portmann , Jérémy Sok , Jan Philip Solovej

This is mostly a survey paper, where we collect results concerning the spectral bounds of deterministic and random Schr\"odinger operators with complex potentials, both on \(\mathbb{R}^d\) and on compact manifolds. The survey part is…

Spectral Theory · Mathematics 2026-05-19 Eduard Stefanescu

Non-self-adjoint Schrodinger operators which correspond to non-symmetric zero-range potentials are investigated. We show that various properties of these operators (eigenvalues, exceptional points, spectral singularities and the property of…

Mathematical Physics · Physics 2015-06-19 P. A. Cojuhari , A. Grod , S. Kuzhel

In [arXiv:0801.0172] we examined a family of periodic Sturm-Liouville problems with boundary and interior singularities which are highly non-self-adjoint but have only real eigenvalues. We now establish Schatten class properties of the…

Spectral Theory · Mathematics 2010-04-15 Lyonell Boulton , Michael Levitin , Marco Marletta

In connection with the Fuglede conjecture, we study the existence of commuting self-adjoint extensions of the partial differential operators on arbitrary, possibly disconnected domains in $\br^d$, the associated unitary group, the spectral…

Functional Analysis · Mathematics 2025-11-24 Piyali Chakraborty , Dorin Ervin Dutkay

Formally symmetric differential operators on weighted Hardy-Hilbert spaces are analyzed, along with adjoint pairs of differential operators. Eigenvalue problems for such operators are rather special, but include many of the classical…

Classical Analysis and ODEs · Mathematics 2019-01-23 Robert Carlson

In this article we discuss a few spectral properties of a paranormal closed operator (not necessarily bounded) defined in a Hilbert space. This class contains closed symmetric operators. First we show that the spectrum of such an operator…

Functional Analysis · Mathematics 2020-05-05 Neeru Bala , G. Ramesh

The self-adjoint matrix Sturm-Liouville operator on a finite interval with a boundary condition in the general form is studied. We obtain asymptotic formulas for the eigenvalues and the weight matrices of the considered operator. These…

Spectral Theory · Mathematics 2019-09-10 Natalia P. Bondarenko

For relatively form-compact perturbations of non-negative selfadjoint operators, we obtain an upper bound on the number of discrete eigenvalues in half-planes separated from the positive real axis. The bound is given in terms of a partial…

Spectral Theory · Mathematics 2026-03-25 Sabine Bögli , Sukrid Petpradittha

The goal of this note is to study the spectrum of a self-adjoint convolution operator in $L^2(\mathbb R^d)$ with an integrable kernel that is perturbed by an essentially bounded real-valued potential tending to zero at infinity. We show…

Spectral Theory · Mathematics 2023-11-16 Denis Borisov , Andrey Piatnitski , Elena Zhizhina

New estimates for eigenvalues of non-self-adjoint multi-dimensional Schr\"{o}dinger operators are obtained in terms of $L_{p}$-norms of the potentials. The results extend and improve those obtained previously. In particular, diverse…

Spectral Theory · Mathematics 2016-02-17 Alexandra Enblom