English
Related papers

Related papers: Understanding truncated non-commutative geometries…

200 papers

We prove lower Dirac eigenvalue bounds for closed surfaces with a spin structure whose Arf invariant equals 1. Besides the area only one geometric quantity enters in these estimates, the spin-cut-diameter which depends on the choice of spin…

Differential Geometry · Mathematics 2007-05-23 Bernd Ammann , Christian Baer

We summarize a recent work on the subject title. The Dirac equation in a curved spacetime depends on a field of coefficients (essentially the Dirac matrices), for which a continuum of different choices are possible. We study the conditions…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Mayeul Arminjon , Frank Reifler

In this paper we introduce and study generally non-self-adjoint realizations of the Dirac operator on an arbitrary finite metric graph. Employing the robust boundary triple framework, we derive, in particular, a variant of the Birman…

Mathematical Physics · Physics 2025-04-09 Markus Holzmann , Václav Růžek , Matěj Tušek

The similarity renormalization group is used to transform Dirac Hamiltonian into a diagonal form, which the upper (lower) diagonal element becomes an operator describing Dirac (anti-)particle. The eigenvalues of the operator are verfied to…

Nuclear Theory · Physics 2015-06-04 Jian-You Guo

Interest on 2 + 1 dimensional electron systems has increased considerably after the realization of novel properties of graphene sheets, in which the behaviour of electrons is effectively described by relativistic equations. Having this fact…

High Energy Physics - Theory · Physics 2012-01-19 Mehmet Ali Olpak

A new concept of geometrization of electromagnetic field is proposed. Instead of the concept of extended field and its point sources, the interacting Maxwellian and Dirac electron--positron fields are considered as a microscopic unified…

High Energy Physics - Theory · Physics 2007-05-23 O. A. Olkhov

As examples of models having interesting constraint structures, we derive a quantum mechanical model from the spatial freezing of a well known relativistic field theory - the chiral Schwinger model. We apply the Hamiltonian constraint…

Mathematical Physics · Physics 2009-07-10 Sudipta Das , Subir Ghosh

Finite real spectral triples are defined to characterise the non-commutative geometry of a fuzzy torus. The geometries are the non-commutative analogues of flat tori with moduli determined by integer parameters. Each of these geometries has…

Quantum Algebra · Mathematics 2024-10-31 John W. Barrett , James Gaunt

We consider deformations of quantum exterior algebras extended by finite groups. Among these deformations are a class of algebras which we call truncated quantum Drinfeld Hecke algebras in view of their relation to classical Drinfeld Hecke…

Rings and Algebras · Mathematics 2018-07-31 Lauren Grimley , Christine Uhl

We construct spectral triples and, in particular, Dirac operators, for the algebra of continuous functions on certain compact metric spaces. The triples are countable sums of triples where each summand is based on a curve in the space.…

Metric Geometry · Mathematics 2007-06-19 Erik Christensen , Cristina Ivan , Michel L. Lapidus

This paper establishes a link between Noncommutative Geometry and canonical quantum gravity. A semi-finite spectral triple over a space of connections is presented. The triple involves an algebra of holonomy loops and a Dirac type operator…

High Energy Physics - Theory · Physics 2009-11-13 Johannes Aastrup , Jesper M. Grimstrup , Ryszard Nest

Any oriented Riemannian manifold with a Spin-structure defines a spectral triple, so the spectral triple can be regarded as a noncommutative Spin-manifold. Otherwise for any unoriented Riemannian manifold there is the two-fold covering by…

Operator Algebras · Mathematics 2017-12-12 Petr Ivankov

We analyze the spectrum of the massless Dirac operator on the 3-torus $\mathbb{T}^3$. It is known that it is possible to calculate this spectrum explicitly, that it is symmetric about zero and that each eigenvalue has even multiplicity.…

Spectral Theory · Mathematics 2021-02-09 Elvis Barakovic , Vedad Pasic

We introduce a family of spectral triples that describe the curved noncommutative two-torus. The relevant family of new Dirac operators is given by rescaling one of two terms in the flat Dirac operator. We compute the dressed scalar…

Quantum Algebra · Mathematics 2018-06-04 Ludwik Dabrowski , Andrzej Sitarz

In this paper, we introduce the spectral Einstein functional for perturbations of Dirac operators on manifolds with boundary. Furthermore, we provide the proof of the Dabrowski-Sitarz-Zalecki type theorems associated with the spectral…

Geometric Topology · Mathematics 2023-12-06 Sining Wei , Yong Wang

The aim of the lectures is to introduce first-year Ph.D. students and research workers to the theory of the Dirac operator, spinor techniques, and their relevance for the theory of eigenvalues in Riemannian geometry. Topics: differential…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Giampiero Esposito

Torsion in a 5D spacetime is considered. In this case gravitation is defined by the 5D metric and the torsion. It is conjectured that torsion is connected with a spinor field. In this case Dirac's equation becomes the nonlinear Heisenberg…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Dzhunushaliev V. D

We investigate manifolds with boundary in noncommutative geometry. Spectral triples associated to a symmetric differential operator and a local boundary condition are constructed. For a classical Dirac operator with a chiral boundary…

Mathematical Physics · Physics 2010-09-30 Bruno Iochum , Cyril Levy

We study the behavior of the spectrum of the Dirac operator on degenerating families of compact Riemannian surfaces, when the length $t$ of a simple closed geodesic shrinks to zero, under the hypothesis that the spin structure along the…

Differential Geometry · Mathematics 2024-09-10 Cipriana Anghel

In this paper, we present a detailed review/analysis of the Dirac quantisation of Hamiltonian systems with constraints. To this end, we use, as a guide, the physical example provided by the dynamics of a solid ball rolling, without…

Quantum Physics · Physics 2026-05-29 M. F. Araujo de Resende , Thales Machado F
‹ Prev 1 4 5 6 7 8 10 Next ›