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Related papers: Improving the Dirac Operator in Lattice QCD

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While the QCD Lagrangian as the whole is only chirally symmetric, its electric part has larger chiral-spin SU(2)_{CS} and SU(2N_F) symmetries. This allows separation of the electric and magnetic interactions in a given reference frame.…

High Energy Physics - Phenomenology · Physics 2020-11-11 L. Ya. Glozman

Lattice chiral fermions are synonymous to the Ginsparg-Wilson relation. Indeed, this relation is satisfied by the overlap, domain wall and perfect action fermion kernel. In a recent work we have shown that it is possible to take a direct RG…

High Energy Physics - Lattice · Physics 2008-11-26 Artan Borici

The microscopic spectral density of the Wilson Dirac operator for two flavor lattice QCD is analyzed. The computation includes the leading order a^2 corrections of the chiral Lagrangian in the microscopic limit. The result is used to…

High Energy Physics - Lattice · Physics 2013-05-30 M. Kieburg , K. Splittorff , J. J. M. Verbaarschot

We investigate the chiral properties of SU(2) gauge theory with six flavors, i.e. six light Dirac fermions in the fundamental representations by lattice simulation, and point out that the spontaneous breakdown of chiral symmetry does not…

High Energy Physics - Lattice · Physics 2013-11-27 M. Hayakawa , K. -I. Ishikawa , S. Takeda , M. Tomii , N. Yamada

We present doubler-free gauge-invariant lattice vector gauge action for some real representations of Wilson gauge fields on an octet of fermions. It is based on a geometric representation of the Dirac equation as an evolution equation on…

High Energy Physics - Lattice · Physics 2007-05-23 I. Schmelzer

We present an adaptive multigrid solver for application to the non-Hermitian Wilson-Dirac system of QCD. The key components leading to the success of our proposed algorithm are the use of an adaptive projection onto coarse grids that…

High Energy Physics - Lattice · Physics 2010-12-02 R. Babich , J. Brannick , R. C. Brower , M. A. Clark , T. A. Manteuffel , S. F. McCormick , J. C. Osborn , C. Rebbi

We report on a lattice simulation result for four-dimensional {\cal N}=1 SU(2) super Yang-Mills theory with the dynamical overlap gluino. We study the spectrum of the overlap Dirac operator at three different gluino masses m=0.2, 0.1 and…

High Energy Physics - Lattice · Physics 2011-11-10 The JLQCD Collaboration , S. -W. Kim , H. Fukaya , S. Hashimoto , H. Matsufuru , J. Nishimura , T. Onogi

Dynamical chiral-symmetry breaking in QCD is studied with the Schwinger-Dyson (SD) formalism based on lattice QCD data, i.e., LQCD-based SD formalism. We extract the SD kernel function $K(p^2)$ in an Ansatz-independent manner from the…

High Energy Physics - Phenomenology · Physics 2009-11-10 Hideaki Iida , Makoto Oka , Hideo Suganuma

We present a gauge-invariant and non-perturbative construction of the Glashow-Weinberg-Salam model on the lattice, based on the lattice Dirac operator satisfying the Ginsparg-Wilson relation. Our construction covers all SU(2) topological…

High Energy Physics - Lattice · Physics 2008-11-26 Daisuke Kadoh , Yoshio Kikukawa

The dominant cutoff effects in lattice QCD with Wilson quarks are proportional to the lattice spacing a. In particular, the isovector axial current satisfies the PCAC relation only up to such effects. Following a suggestion of Symanzik,…

High Energy Physics - Lattice · Physics 2009-10-28 Martin Luescher , Stefan Sint , Rainer Sommer , Peter Weisz

We investigate the spectral properties of the Wilson Dirac operator in quenched QCD in the microscopic regime. We distinguish the topological sectors using the index as determined by the Wilson flow method. Consequently, the distributions…

High Energy Physics - Lattice · Physics 2012-01-04 Albert Deuzeman , Urs Wenger , Jair Wuilloud

Eigenvalues of the Hermitian Wilson-Dirac operator are of special interest in several lattice QCD simulations, e.g., for noise reduction when evaluating all-to-all propagators. In this paper we present a Davidson-type eigensolver that…

High Energy Physics - Lattice · Physics 2020-10-28 Andreas Frommer , Karsten Kahl , Francesco Knechtli , Matthias Rottmann , Artur Strebel , Ian Zwaan

The $SU(3)\otimes SU(2) \otimes U(1)$ standard model maps smoothly onto a conventional Wilson lattice gauge formalism, including the parity violation of the weak interactions. The formulation makes use of the pseudo-reality of the weak…

High Energy Physics - Lattice · Physics 2025-01-06 Michael Creutz

We determine the free field hypercubic Dirac operator which is optimally close to satisfying the Ginsparg-Wilson relation. Inserting this operator into the overlap formula, we show that the analytic locality bound on the resulting overlap…

High Energy Physics - Lattice · Physics 2009-11-10 David H. Adams

We present results for the non-perturbative determination of the improvement and renormalization factors of the isovector axial current for lattice QCD with two flavors of dynamical Wilson quarks. The improvement and normalization…

High Energy Physics - Lattice · Physics 2007-05-23 Roland Hoffmann , Michele Della Morte , Francesco Knechtli , Rainer Sommer , Ulli Wolff

We present numerical results for the 2-flavour Schwinger model with dynamical chiral lattice fermions. We insert an approximately chiral hypercube Dirac operator into the overlap formula to construct the overlap hypercube operator. This is…

High Energy Physics - Lattice · Physics 2012-04-26 Wolfgang Bietenholz , Ivan Hip , Stanislav Shcheredin , Jan Volkholz

We study topological aspects of the QCD vacuum structure in SU(2) lattice gauge theory with the abelian gauge fixing. The index of the Dirac operator is measured by using the Wilson fermion in the quenched approximation. We find…

High Energy Physics - Lattice · Physics 2009-10-30 Shoichi Sasaki , Osamu Miyamura

We formulate a model of relativistic fermions moving in two Euclidean dimensions based on a tight-binding model of graphene. The eigenvalue spectrum of the resulting Dirac operator is solved numerically in smooth U(1) gauge field…

High Energy Physics - Lattice · Physics 2010-04-15 Dipankar Chakrabarti , Simon Hands , Antonio Rago

We present simulation results for lattice QCD with chiral fermions in small volumes, where the epsilon-expansion of chiral perturbation theory applies. Our data for the low lying Dirac eigenvalues, as well as mesonic correlation functions,…

High Energy Physics - Lattice · Physics 2009-11-11 W. Bietenholz , T. Chiarappa , K. Jansen , K. -I. Nagai , S. Shcheredin

We study characteristic features of the eigenvalues of the Wilson-Dirac operator in topologically non-trivial gauge field configurations by examining complete spectra of the fermion matrix. In particular we discuss the role of eigenvectors…

High Energy Physics - Lattice · Physics 2009-10-30 Christof Gattringer , Ivan Hip