English
Related papers

Related papers: Keller-type bounds for Dirac operators perturbed b…

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

This paper is devoted to a general min-max characterization of the eigenvalues in a gap of the essential spectrum of a self-adjoint unbounded operator. We prove an abstract theorem, then we apply it to the case of Dirac operators with a…

Spectral Theory · Mathematics 2022-06-14 Jean Dolbeault , Maria J. Esteban , Eric Séré

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

In K\"ahler-Einstein case of positive scalar curvature and even complex dimension, an improved lower bound for the first eigenvalue of the Dirac operator is given. It is shown by a general construction that there are manifolds for which…

Differential Geometry · Mathematics 2009-12-09 K. -D. Kirchberg

We derive a lower bound on the location of global extrema of eigenfunctions for a large class of non-local Schr\"odinger operators in convex domains under Dirichlet exterior conditions, featuring the symbol of the kinetic term, the strength…

Spectral Theory · Mathematics 2019-01-10 Anup Biswas , József Lőrinczi

We study one-dimensional Schr\"odinger operators with complex measures as potentials and present an improved criterion for absence of eigenvalues which involves a weak local periodicity condition. The criterion leads to sharp quantitative…

Spectral Theory · Mathematics 2016-06-28 Christian Seifert , Hendrik Vogt

We prove quantitative bounds on the eigenvalues of non-selfadjoint unbounded operators obtained from selfadjoint operators by a perturbation that is relatively-Schatten. These bounds are applied to obtain new results on the distribution of…

Spectral Theory · Mathematics 2009-09-10 Michael Demuth , Marcel Hansmann , Guy Katriel

We investigate a two-dimensional Schr\"odinger operator, $-h^2 \Delta +iV(x)$, with a purely complex potential $iV(x)$. A rigorous definition of this non-selfadjoint operator is provided for bounded and unbounded domains with common…

Spectral Theory · Mathematics 2020-01-03 D. S. Grebenkov , B. Helffer

We prove a sharp Hardy-type inequality for the Dirac operator. We exploit this inequality to obtain spectral properties of the Dirac operator perturbed with Hermitian matrix-valued potentials $\mathbf V$ of Coulomb type: we characterise its…

Analysis of PDEs · Mathematics 2018-10-03 Biagio Cassano , Fabio Pizzichillo , Luis Vega

We extend several classical eigenvalue estimates for Dirac operators on compact manifolds to noncompact, even incomplete manifolds. This includes Friedrich's estimate for manifolds with positive scalar curvature as well as the author's…

Differential Geometry · Mathematics 2009-07-16 Christian Baer

We study the spectral properties of a Schr\"odinger operator, in presence of a confining potential given by the distance squared from a fixed compact potential well. We prove continuity estimates on both the eigenvalues and the eigenstates,…

Analysis of PDEs · Mathematics 2025-05-19 Chiara Alessi , Lorenzo Brasco , Michele Miranda

We propose a rigorous method for computing two-sided eigenvalue bounds of the Schr\"odinger operator $H=-\Delta+V$ with a confining potential on $\mathbb{R}^2$. The method combines domain truncation to a finite disk $D(R)$ on which the…

Numerical Analysis · Mathematics 2026-04-14 Xuefeng Liu

Boundedness of wave operators for Schr\"odinger operators in one space dimension for a class of singular potentials, admitting finitely many Dirac delta distributions, is proved. Applications are presented to, for example, dispersive…

Analysis of PDEs · Mathematics 2021-10-01 Vincent Duchêne , Jeremy L. Marzuola , Michael I. Weinstein

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

We consider non-self-adjoint Schr\"{o}dinger operators $H_{{\rm c}}=-\Delta+V_{{\rm c}}$ (resp. $H_{{\rm r}}=-\Delta+V_{{\rm r}}$) acting in $L^2(\mathbb R^d)$, $d\ge 1$, with dilation analytic complex (resp. real) potentials. We were able…

Spectral Theory · Mathematics 2020-11-16 Norihiro Someyama

The problem of self-adjoint extensions of Dirac-type operators in manifolds with boundaries is analysed. The boundaries might be regular or non-regular. The latter situation includes point-like interactions, also called delta-like…

Mathematical Physics · Physics 2017-05-29 J. M. Pérez-Pardo

We prove new lower bounds for the first eigenvalue of the Dirac operator on compact manifolds whose Weyl tensor or curvature tensor, respectively, is divergence free. In the special case of Einstein manifolds, we obtain estimates depending…

Differential Geometry · Mathematics 2009-11-07 Thomas Friedrich , Klaus-Dieter Kirchberg

Using Weitzenb\"ock techniques on any compact Riemannian spin manifold we derive inequalities that involve a real parameter and join the eigenvalues of the Dirac operator with curvature terms. The discussion of these inequalities yields…

Differential Geometry · Mathematics 2009-11-10 K. -D. Kirchberg

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

We consider Schr\"odinger operators in $\mathbb R^d$ with complex potentials supported on a hyperplane and show that all eigenvalues lie in a disk in the complex plane with radius bounded in terms of the $L^p$ norm of the potential with…

Spectral Theory · Mathematics 2015-12-31 Rupert L. Frank