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Related papers: Quasi-Dirac Operators and Quasi-Fermions

200 papers

We construct a Dirac operator on the quantum sphere $S^2_q$ which is covariant under the action of $SU_q(2)$. It reduces to Watamuras' Dirac operator on the fuzzy sphere when $q\to 1$. We argue that our Dirac operator may be useful in…

High Energy Physics - Theory · Physics 2009-11-07 A. Pinzul , A. Stern

We find and classify possible equivariant spin structures with Dirac operators on the noncommutative torus, proving that similarly as in the classical case the spectrum of the Dirac operator depends on the spin structure.

Quantum Algebra · Mathematics 2018-06-04 Mario Paschke , Andrzej Sitarz

Motivated by examples obtained from conformal deformations of spectral triples and a spectral triple construction on quantum cones we propose a new twisted reality condition for the Dirac operator.

Quantum Algebra · Mathematics 2018-06-04 Tomasz Brzeziński , Nicola Ciccoli , Ludwik Dąbrowski , Andrzej Sitarz

We classify the twists of almost commutative spectral triples that keep the Hilbert space and the Dirac operator untouched. The involved twisting operator is shown to be the product of the grading of a manifold by a finite dimensional…

Mathematical Physics · Physics 2021-12-14 Manuele Filaci , Pierre Martinetti

A Dirac operator D on the standard Podles sphere is defined and investigated. It yields a spectral triple such that |D|^{-z} is of trace class for Re z>0. Commutators with the Dirac operator give the distinguished 2-dimensional covariant…

Quantum Algebra · Mathematics 2007-07-23 Konrad Schmuedgen , Elmar Wagner

Specific properties, such as surface Fermi arcs, features of quantum oscillations and of various responses to a magnetic field, distinguish Dirac semimetals from ordinary materials. These properties are determined by Dirac points at which a…

Mesoscale and Nanoscale Physics · Physics 2024-09-17 Grigorii P. Mikitik

The spectral torsion is defined by three vector fields and Dirac operators and the noncommutative residue. Motivated by the spectral torsion and the one form rescaled Dirac operator, we give some new spectral torsion which is the extension…

Differential Geometry · Mathematics 2025-05-30 Jian Wang , Yong Wang

We construct a canonical geometrically realised Connes spectral triple or `Dirac operator' $D\!\!\!/$ from the data of a quantum metric $g\in \Omega^1\otimes_A\Omega^1$ and quantum Levi-Civita bimodule connection, at the pre-Hilbert space…

Quantum Algebra · Mathematics 2023-05-16 Shahn Majid

Spectral triples over noncommutative principal $\T^n$-bundles are studied, extending recent results about the noncommutative geometry of principal U(1)-bundles. We relate the noncommutative geometry of the total space of the bundle with the…

Quantum Algebra · Mathematics 2013-08-23 Alessandro Zucca , Ludwik Dabrowski

We study various properties of quasimodular forms by using their connections with Jacobi-like forms and pseudodifferential operators. Such connections are made by identifying quasimodular forms for a discrete subgroup $\G$ of $SL(2, \bR)$…

Number Theory · Mathematics 2010-07-29 YoungJu Choie , Minho Lee

We discuss some properties of zero and near-zero modes of the Dirac operator, as observed in a recent simulation of 2-flavor QCD. The quarks have been implemented with the so-called Chirally Improved Dirac operator, which obeys the…

High Energy Physics - Lattice · Physics 2007-05-23 C. B. Lang , Pushan Majumdar , Wolfgang Ortner

We construct wave functions and Dirac operator of spin $1/2$ fermions on quantum four-spheres. The construction can be achieved by the q-deformed differential calculus which is manifestly $SO(5)_q$ covariant. We evaluate the engenvalue of…

High Energy Physics - Theory · Physics 2007-05-23 K. Ohta , H. Suzuki

Quasiperiodic Jacobi operators arise as mathematical models of quasicrystals and in more general studies of structures exhibiting aperiodic order. The spectra of these self-adjoint operators can be quite exotic, such as Cantor sets, and…

Spectral Theory · Mathematics 2014-12-30 Charles Puelz , Mark Embree , Jake Fillman

We present examples of equivariant noncommutative Lorentzian spectral geometries. The equivariance with respect to a compact isometry group (or quantum group) allows to construct the algebraic data of a version of spectral triple geometry…

Mathematical Physics · Physics 2007-05-23 Mario Paschke , Andrzej Sitarz

We demonstrate that neutral Dirac particles in external electric fields, which are equivalent to generalized Dirac oscillators, are physical examples of quasi-exactly solvable systems. Electric field configurations permitting quasi-exact…

High Energy Physics - Theory · Physics 2015-06-26 Choon-Lin Ho , Pinaki Roy

When aiming to apply mathematical results of non-commutative geometry to physical problems the question arises how they translate to a context in which only a part of the spectrum is known. In this article we aim to detect when a…

Mathematical Physics · Physics 2020-03-18 Lisa Glaser , Abel Stern

We study spectral properties of second order elliptic operators with periodic coefficients in dimension two. These operators act in periodic simply-connected waveguides, with either Dirichlet, or Neumann, or the third boundary condition.…

Spectral Theory · Mathematics 2007-05-23 E. Shargorodsky , A. V. Sobolev

We determine what should correspond to the Dirac operator on certain quantized hermitian symmetric spaces and what its properties are. A new insight into the quantized wave operator is obtained.

Quantum Algebra · Mathematics 2007-05-23 Hans Plesner Jakobsen

We construct a family of self-adjoint operators D_N which have compact resolvent and bounded commutators with the coordinate algebra of the quantum projective space CP_q(l), for any l>1 and 0<q<1. They provide 0^+ dimensional equivariant…

Quantum Algebra · Mathematics 2010-06-01 Francesco D'Andrea , Ludwik Dabrowski

A class of real spectral triples that are similar in structure to a Riemannian manifold but have a finite-dimensional Hilbert space is defined and investigated, determining a general form for the Dirac operator. Examples include fuzzy…

Mathematical Physics · Physics 2015-09-02 John W. Barrett