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Related papers: Dirac Operators on Non-Compact Orbifolds

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A completeness theorem is proved involving a system of integro-differential equations with some $\lambda$-depending boundary conditions. Also some sufficient conditions for the root functions to form a Riesz basis are established.

Functional Analysis · Mathematics 2013-09-27 Seppo Hassi , Leonid Oridoroga

We consider Dirac operators on the half-line, subject to generalised infinite-mass boundary conditions. We derive sufficient conditions which guarantee the stability of the spectrum against possibly non-self-adjoint potential perturbations…

Spectral Theory · Mathematics 2025-02-05 David Kramar , David Krejcirik

This paper studies Dirac operators on end-periodic spin manifolds of dimension at least 4. We provide a sufficient condition for such an operator to be Fredholm for a generic end-periodic metric; this condition is shown to be necessary in…

Geometric Topology · Mathematics 2007-05-23 Daniel Ruberman , Nikolai Saveliev

We look at smooth manifolds equipped with a possibly singular Riemannian metric. We give sufficient conditions for the existence of scalar curvature measures and Dirac operators.

Differential Geometry · Mathematics 2025-12-24 John Lott

A Dirac-type operator on a complete Riemannian manifold is of Callias-type if its square is a Schr\"{o}dinger-type operator with a potential uniformly positive outside of a compact set. We develop the theory of Callias-type operators…

Differential Geometry · Mathematics 2018-03-28 Simone Cecchini

On a compact spin manifold we study the space of Riemannian metrics for which the Dirac operator is invertible. The first main result is a surgery theorem stating that such a metric can be extended over the trace of a surgery of codimension…

Differential Geometry · Mathematics 2011-07-21 Mattias Dahl

A Dirac operator on a complete manifold is Fredholm if it is invertible outside a compact set. Assuming a compact group to act on all relevant structure, and the manifold to have a warped product structure outside such a compact set, we…

Differential Geometry · Mathematics 2023-03-20 Peter Hochs , Hang Wang

A Dirac operator is presented that will yield a 1+ summable regular even spectral triple for all noncommutative compact surfaces defined as subalgebras of the Toeplitz algebra. Connes' conditions for noncommutative spin geometries are…

Operator Algebras · Mathematics 2020-02-26 Fredy Díaz García , Elmar Wagner

This paper is a follow-up on the \emph{noncommutative differential geometry on infinitesimal spaces} [15]. In the present work, we extend the algebraic convergence from [15] to the geometric setting. On the one hand, we reformulate the…

Numerical Analysis · Mathematics 2023-09-13 Damien Tageddine , Jean-Christophe Nave

We study extensions of direct sums of symmetric operators $S=\oplus_{n\in\mathbb{N}} S_n$. In general there is no natural boundary triplet for $S^*$ even if there is one for every $S_n^*$, $n\in\mathbb{N}$. We consider a subclass of…

Spectral Theory · Mathematics 2018-06-12 Hannes Gernandt , Carsten Trunk

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

We give results about the L^2 kernel and the spectrum of the Dirac operator on a complete Riemannian manifold which is conformally equivalent to the interior of a Riemannian manifold with nonempty boundary.

Differential Geometry · Mathematics 2007-05-23 John Lott

We develop a theory of regularity for Dirac operators with uniformly locally square-integrable operator data. This is motivated by Stahl--Totik regularity for orthogonal polynomials and by recent developments for continuum Schr\"odinger…

Spectral Theory · Mathematics 2020-12-24 Benjamin Eichinger , Ethan Gwaltney , Milivoje Lukić

In order to extend the spectral action principle to non-compact spaces, we propose a framework for spectral triples where the algebra may be non-unital but the resolvent of the Dirac operator remains compact. We show that an example is…

High Energy Physics - Theory · Physics 2009-07-10 Raimar Wulkenhaar

The spectral propinquity is a distance, up to unitary equivalence, on the class of metric spectral triples. We prove in this paper that if a sequence of metric spectral triples converges for the propinquity, then the spectra of the Dirac…

Operator Algebras · Mathematics 2024-07-15 Frederic Latremoliere

We investigate examples of quasi-spectral triples over two-dimensional commutative sphere, which are obtained by modifying the order-one condition. We find equivariant quasi-Dirac operators and prove that they are in a topologically…

Mathematical Physics · Physics 2018-06-04 Andrzej Sitarz

We carry out the spectral analysis of matrix valued perturbations of 3-dimensional Dirac operators with variable magnetic field of constant direction. Under suitable assumptions on the magnetic field and on the pertubations, we obtain a…

Mathematical Physics · Physics 2015-06-26 Serge Richard , Rafael Tiedra de Aldecoa

We prove that the nodal set (zero set) of a solution of a generalized Dirac equation on a Riemannian manifold has codimension 2 at least. If the underlying manifold is a surface, then the nodal set is discrete. We obtain a quick proof of…

dg-ga · Mathematics 2009-10-30 Christian Baer

Quasi-one-dimensional stochastic Dirac operators with an odd number of channels, time reversal symmetry but otherwise efficiently coupled randomness are shown to have one conducting channel and absolutely continuous spectrum of multiplicity…

Mathematical Physics · Physics 2011-01-25 Christian Sadel , Hermann Schulz-Baldes

We investigate the self-adjointness of the two dimensional Dirac operator with infinite mass boundary conditions on an unbounded domain with an infinite number of corners. We prove that if the domain has no concave corners, then the…

Analysis of PDEs · Mathematics 2024-08-06 Miguel Camarasa , Fabio Pizzichillo