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Related papers: Quasi-Dirac Operators and Quasi-Fermions

200 papers

Starting with a Dirac operator on a configuration space of $SU(2)$ gauge connections we consider its fluctuations with inner automorphisms. We show that a certain type of twisted inner fluctuations leads to a Dirac operator whose square…

High Energy Physics - Theory · Physics 2025-01-03 Johannes Aastrup , Jesper M. Grimstrup

New exact upper and lower bounds are derived on the spectrum of the square of the hermitian Wilson Dirac operator. It is hoped that the derivations and the results will be of help in the search for ways to reduce the cost of simulations…

High Energy Physics - Lattice · Physics 2009-07-09 H. Neuberger

We establish a vanishing result for indices of certain twisted Dirac operators on $\text{Spin}^c$-manifolds with non-abelian Lie-group actions. We apply this result to study non-abelian symmetries of quasitoric manifolds. We give upper…

Geometric Topology · Mathematics 2014-10-01 Michael Wiemeler

We study a canonical class of perturbations of Dirac operators that are defined in any dimension and on any Hermitian Clifford module bundle. These operators generalize the 2-dimensional Jackiw-Rossi operator, which describes electronic…

Differential Geometry · Mathematics 2025-03-20 Ákos Nagy

We review a procedure of factorizing the Minkowski space Dirac operator over a~suitable superspace, discuss its Euclidean space version and apply the worked out formalism in the case od an almost-commutative Dirac operator. The presented…

High Energy Physics - Theory · Physics 2021-12-22 Dominik Ciurla , Leszek Hadasz , Thomas Williams

We investigate the quasiparticles of a single nodal ring semimetal SrAs$_3$ through axis-resolved magneto-optical measurements. We observe three types of Landau levels scaling as $\varepsilon \sim \sqrt{B}$, $\varepsilon \sim B^{2/3}$, and…

Materials Science · Physics 2025-08-21 Jiwon Jeon , Taehyeok Kim , Jiho Jang , Hoil Kim , Mykhaylo Ozerov , Jun Sung Kim , Hongki Min , Eunjip Choi

Equivariance under the action of Uq(so(5)) is used to compute the left regular and (chiral) spinorial representations of the algebra of the orthogonal quantum 4-sphere S^4_q. These representations are the constituents of a spectral triple…

Quantum Algebra · Mathematics 2008-02-28 Francesco D'Andrea , Ludwik Dabrowski , Giovanni Landi

In this article we construct the chirality and Dirac operators on noncommutative AdS_2. We also derive the discrete spectrum of the Dirac operator which is important in the study of the spectral triple associated with AdS_2. It is shown…

High Energy Physics - Theory · Physics 2009-11-10 H. Fakhri , A. Imaanpur

We solve for quantum-geometrically realised spectral triples or `Dirac operators' on the noncommutative torus $\Bbb C_\theta[T^2]$ and on the algebra $M_2(\Bbb C)$ of $2\times 2$ matrices with their standard quantum metrics and associated…

Quantum Algebra · Mathematics 2023-06-21 E. Lira-Torres , S. Majid

Two-dimensional and three-dimensional massless Dirac fermions can form a sequence of quasibound states with an attractive charged impurity. These quasibound states exhibit a discrete scaling symmetry, i.e., the energy ratio between two…

Mesoscale and Nanoscale Physics · Physics 2018-11-28 Mingyuan Sun

We develop relative oscillation theory for one-dimensional Dirac operators which, rather than measuring the spectrum of one single operator, measures the difference between the spectra of two different operators. This is done by replacing…

Spectral Theory · Mathematics 2010-08-10 Robert Stadler , Gerald Teschl

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

In this paper, we study the spectrality of the non-self-adjoint Dirac operator L(Q) with a complex-valued periodic matrix potential Q. We establish a condition on the off-diagonal elements of the matrix Q under which L(Q) is an…

Spectral Theory · Mathematics 2026-03-04 O. A. Veliev

The pseudospectra (or spectral instability) of non-selfadjoint operators is a topic of current interest in applied mathematics. In fact, for non-selfadjoint operators the resolvent could be very large outside the spectrum, making the…

Analysis of PDEs · Mathematics 2010-03-05 Nils Dencker

Jacobi operators appear as kinetic operators of several classes of noncommutative field theories (NCFT) considered recently. This paper deals with the case of bounded Jacobi operators. A set of tools mainly issued from operator and spectral…

Mathematical Physics · Physics 2015-08-07 Antoine Géré , Jean-Christophe Wallet

Geometric properties of operators of quantum Dirac constraints and physical observables are studied in semiclassical theory of generic constrained systems. The invariance transformations of the classical theory -- contact canonical…

General Relativity and Quantum Cosmology · Physics 2008-02-03 A. O. Barvinsky

In this paper we study spectral properties of the Neumann-Laplace operator in planar quasiconformal regular domains $\Omega\subset\mathbb R^2$. This study is based on the quasiconformal theory of composition operators on Sobolev spaces.…

Analysis of PDEs · Mathematics 2017-03-13 V. Gol'dshtein , V. Pchelintsev , A. Ukhlov

We develop notions of twisted spinor bundle and twisted pre-quantum bundle on quasi-Hamiltonian G-spaces. The main result of this paper is that we construct a Dirac operator with index given by positive energy representation of loop group.…

Symplectic Geometry · Mathematics 2016-06-29 Yanli Song

We give a simple proof of the fact that every diagonalizable operator that has a real spectrum is quasi-Hermitian and show how the metric operators associated with a quasi-Hermitian Hamiltonian are related to the symmetry generators of an…

Quantum Physics · Physics 2009-11-13 Ali Mostafazadeh

The aim of the present paper is to analyse the spectrum of Laplace and Dirac type operators on metric graphs. In particular, we show for equilateral graphs how the spectrum (up to exceptional eigenvalues) can be described by a natural…

Mathematical Physics · Physics 2008-01-15 Olaf Post