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Related papers: Dirac operator normality and chiral properties

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We construct a family of Ginsparg-Wilson Hamiltonians with improved chiral properties, starting from a construction of Creutz-Horvath-Neuberger that provides a doubler-free Hamiltonian lattice regularization for Dirac fermions in even…

High Energy Physics - Lattice · Physics 2025-05-28 Hersh Singh

We show that even if a lattice Dirac operator satisfies the conditions consisting of locality, free of species doublings, correct continuum behavior, $\gm5$-hermiticity and the Ginsparg-Wilson relation, it does not necessarily have exact…

High Energy Physics - Lattice · Physics 2007-05-23 Ting-Wai Chiu

A perturbative study of a general class of lattice Dirac operators is reported, which is based on an algebraic realization of the Ginsparg-Wilson relation in the form $\gamma_{5}(\gamma_{5}D)+(\gamma_{5}D)\gamma_{5} =…

High Energy Physics - Lattice · Physics 2016-09-01 Kazuo Fujikawa , Masato Ishibashi

For relativistic closed systems, an operator is explained which has as stationary eigenvalues the squares of the total cms energies, while the wave function has only half as many components as the corresponding Dirac wave function. The…

High Energy Physics - Theory · Physics 2007-05-23 Hartmut Pilkuhn

A new class of lattice Dirac operators which satisfy the index theorem have been recently proposed on the basis of the algebraic relation $\gamma_{5}(\gamma_{5}D) + (\gamma_{5}D)\gamma_{5} = 2a^{2k+1}(\gamma_{5}D)^{2k+2}$. Here $k$ stands…

High Energy Physics - Lattice · Physics 2009-10-31 Kazuo Fujikawa , Masato Ishibashi

The gauge covariant lattice Dirac operator D which has recently been proposed by Neuberger satisfies the Ginsparg-Wilson relation and thus preserves chiral symmetry. The operator also avoids a doubling of fermion species, but its locality…

High Energy Physics - Lattice · Physics 2011-07-19 P. Hernández , K. Jansen , M. Lüscher

We study the spectrum of the QCD Dirac operator near zero virtuality for $N_c =2$. According to a universality argument, it can be described by a random matrix theory with the chiral structure of QCD, but with $real$ matrix elements. Using…

High Energy Physics - Theory · Physics 2009-10-28 Jacobus Verbaarschot

We evaluate chiral anomaly on the noncommutative torus with the overlap Dirac operator satisfying the Ginsparg-Wilson relation in arbitrary even dimensions. Utilizing a topological argument we show that the chiral anomaly is combined into a…

High Energy Physics - Theory · Physics 2009-11-07 Satoshi Iso , Keiichi Nagao

We discuss the computational problems when analyzing general, non-hermitian matrices and in particular the un-modified Wilson lattice Dirac operator. We report on our experiences with the Implicitly Restarted Arnoldi Method. The eigenstates…

High Energy Physics - Lattice · Physics 2009-10-31 Christof Gattringer , Ivan Hip

The coupling of spin 0 and spin 1 external fields to Dirac fermions defines a theory which displays gauge chiral symmetry. Quantum mechanically, functional integration of the fermions yields the determinant of the Dirac operator, known as…

High Energy Physics - Theory · Physics 2008-12-18 L. L. Salcedo

We show that, under certain general assumptions, any sensible lattice Dirac operator satisfies a generalized form of the Ginsparg-Wilson relation (GWR). Those assumptions, on the other hand, are mostly dictated by large momentum behaviour…

High Energy Physics - Lattice · Physics 2009-10-31 C. D. Fosco , M. Teper

The Wilson formulation of fermions in lattice gauge theory provides a unified description of the chiral anomalies in the standard model. The discrete Dirac operator diagonalizes into a series of two by two blocks. In each block the possible…

High Energy Physics - Lattice · Physics 2026-04-22 Michael Creutz

I study the consequences of chiral symmetry restoration for the Dirac spectrum in finite-temperature gauge theories in the two-flavor chiral limit, using Ginsparg--Wilson fermions on the lattice. I prove that chiral symmetry is restored at…

High Energy Physics - Lattice · Physics 2025-10-29 Matteo Giordano

We clarify the questions rised by a recent example of a lattice Dirac operator found by Chiu. We show that this operator belongs to a class based on the Cayley transformation and that this class on the finite lattice generally does not…

High Energy Physics - Lattice · Physics 2010-02-03 Werner Kerler

Instead of the Ginsparg-Wilson relation only generalized chiral symmetry is required. The resulting much larger class of Dirac operators for massless fermions is investigated and a general construction for them is given. It is also shown…

High Energy Physics - Lattice · Physics 2009-11-07 Werner Kerler

We discuss within the framework of the ERG how chiral symmetry is realized in a linear $\sigma$ model. A generalized Ginsparg-Wilson relation is obtained from the Ward-Takahashi identities for the Wilson action assumed to be bilinear in the…

High Energy Physics - Theory · Physics 2011-05-05 Yoshio Echigo , Yuji Igarashi

We present a formulation of chiral gauge theories, which admits more general spectra of Dirac operators and reveals considerably more possibilities for the structure of the chiral projections. Our two forms of correlation functions both…

High Energy Physics - Lattice · Physics 2009-11-10 Werner Kerler

We present a detailed study of the interplay between chiral symmetry and spectral properties of the Dirac operator in lattice gauge theories. We consider, in the framework of the Schwinger model, the fixed point action and a fermion action…

High Energy Physics - Lattice · Physics 2009-10-31 F. Farchioni , I. Hip , C. B. Lang , M. Wohlgenannt

We study localization and chirality properties of eigenvectors of the lattice Dirac operator. In particular we focus on the dependence of our observables on the size of the corresponding eigenvalue, which allows us to study the transition…

High Energy Physics - Lattice · Physics 2008-11-26 Christof Gattringer , Meinulf Goeckeler , P. E. L. Rakow , Stefan Schaefer , Andreas Schaefer

We present a general formulation of chiral gauge theories, which admits Dirac operators with more general spectra, reveals considerably more possibilities for the structure of the chiral projections, and nevertheless allows appropriate…

High Energy Physics - Lattice · Physics 2007-05-23 Werner Kerler