English
Related papers

Related papers: Axial anomaly with the overlap-Dirac operator in a…

200 papers

We study a three-dimensional non-compact QED with a single two-component massless fermion and two infinitely massive regulator fermions of half the charge using lattice overlap formalism. The parity anomaly is expected to cancel exactly…

High Energy Physics - Lattice · Physics 2018-08-01 Nikhil Karthik , Rajamani Narayanan

Taking into account of the boundary condition in the fifth direction which is derived from the lattice Wilson fermion, we develop a theory of five-dimensional fermion with kink-like and homogeneous masses in finite extent of the fifth…

High Energy Physics - Lattice · Physics 2016-08-31 T. Kawano , Y. Kikukawa

We investigate the properties of self-adjointness of a two-dimensional Dirac operator on an infinite sector with infinite mass boundary conditions and in presence of a Coulomb-type potential with the singularity placed on the vertex. In the…

Analysis of PDEs · Mathematics 2022-07-20 Biagio Cassano , Matteo Gallone , Fabio Pizzichillo

We study the eigenvalue spectrum of different lattice Dirac operators (staggered, fixed point, overlap) and discuss their dependence on the topological sectors. Although the model is 2D (the Schwinger model with massless fermions) our…

High Energy Physics - Lattice · Physics 2015-06-25 F. Farchioni , I. Hip , C. B. Lang

We compute the axial anomaly for the Taub-NUT metric on $R^4$. We show that the axial anomaly for the generalized Taub-NUT metrics introduced by Iwai and Katayama is finite, although the Dirac operator is not Fredholm. We show that the…

Mathematical Physics · Physics 2009-11-11 Sergiu Moroianu , Mihai Visinescu

We discuss the continuum limit of discrete Dirac operators on the square lattice in $\mathbb R^2$ as the mesh size tends to zero. To this end, we propose the most natural and simplest embedding of $\ell^2(\mathbb Z_h^d)$ into $L^2(\mathbb…

Mathematical Physics · Physics 2023-05-22 Karl Michael Schmidt , Tomio Umeda

Using perturbation theory in the Euclidean (imaginary time) formalism as well as the non-perturbative Fujikawa method, we verify that the chiral anomaly equation remains unaffected in the presence of nonzero chemical potential, $\mu$. We…

High Energy Physics - Lattice · Physics 2010-03-04 R. V. Gavai , Sayantan Sharma

A new lattice action is proposed for the overlap Dirac matrix with nonzero chemical potential. It is shown to preserve the full chiral invariance for all values of lattice spacing exactly. It is further demonstrated to arise in the domain…

High Energy Physics - Lattice · Physics 2015-06-11 Rajiv V. Gavai , Sayantan Sharma

We consider supersymmetric quantum mechanical systems in arbitrary dimensions on curved spaces with nontrivial gauge fields. The square of the Dirac operator serves as Hamiltonian. We derive a relation between the number of supercharges…

High Energy Physics - Theory · Physics 2009-11-10 A. Kirchberg , J. D. Laenge , A. Wipf

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

The so-called Dirac oscillator was proposed as a modification of the free Dirac equation which reproduces many of the properties of the simple harmonic oscillator but accompanied by a strong spin-orbit coupling term. It has yet to be…

Quantum Physics · Physics 2014-09-19 C. R. Hagen

We investigate relations between the chiral susceptibility and axial $U(1)$ anomaly in lattice QCD at high temperatures. Employing the exactly chiral symmetric Dirac operator, we separate the purely axial $U(1)$ breaking effect in the…

High Energy Physics - Lattice · Physics 2024-03-27 S. Aoki , Y. Aoki , H. Fukaya , S. Hashimoto , I. Kanamori , T. Kaneko , Y. Nakamura , K. Suzuki , D. Ward

Using the grassman-number-integral representation of the vacuum overlap formula, it is shown that the symmetry of the auxiliary quantum fermion system in the overlap formalism induces exact chiral symmetry of the action of the type given by…

High Energy Physics - Lattice · Physics 2007-05-23 Yoshio Kikukawa , Atsushi Yamada

We prove a dichotomy of almost periodicity for reflectionless one-dimensional Dirac operators whose spectra satisfy certain geometric conditions, extending work of Volberg--Yuditskii. We also construct a weakly mixing Dirac operator with a…

Spectral Theory · Mathematics 2025-09-24 Nyah Davis , íris Emilsdóttir , Long Li , Hangqi Liang

Dirac fermions coupled to gauge fields can exhibit the chiral anomaly even on a finite spatial lattice. A careful description of this phenomenon yields new insights into the nature of spin-charge relations and on-site symmetries (symmetries…

High Energy Physics - Theory · Physics 2018-11-16 Djordje Radicevic

The Dirac equation with mass and axial chemical potential is solved analytically obtaining the mode spinors and corresponding projection operators giving the spectral representations of the principal conserved operators. In this framework,…

High Energy Physics - Theory · Physics 2025-06-24 Ion I. Cotaescu

When trying to cast the free fermion in the framework of functorial field theory, its chiral anomaly manifests in the fact that it assigns the determinant of the Dirac operator to a top-dimensional closed spin manifold, which is not a…

Differential Geometry · Mathematics 2025-10-07 Matthias Ludewig , Saskia Roos

The overlap formula for the chiral determinant is presented and the realization of gauge anomalies and gauge field toplogy in this context is discussed. The ability of the overlap formalism to deal with supersymmetric theories and…

High Energy Physics - Lattice · Physics 2009-09-25 Rajamani Narayanan

We propose a six-dimensional regularization of four dimensional chiral gauge theories. We consider a massive Dirac fermion in six dimensions with two different operators having domain-wall profiles in the fifth and the sixth directions,…

High Energy Physics - Lattice · Physics 2017-05-18 Hidenori Fukaya , Tetsuya Onogi , Shota Yamamoto , Ryo Yamamura

On a compact globally hyperbolic Lorentzian spin manifold with smooth spacelike Cauchy boundary the (hyperbolic) Dirac operator is known to be Fredholm when Atiyah-Patodi-Singer boundary conditions are imposed. In this paper we investigate…

Differential Geometry · Mathematics 2017-07-17 Christian Baer , Sebastian Hannes