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Related papers: Quenched Chiral Artifacts for Wilson-Dirac Fermion…

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The behavior of quenched Dirac spectra of two-dimensional lattice QCD is consistent with spontaneous chiral symmetry breaking which is forbidden according to the Coleman-Mermin-Wagner theorem. One possible resolution of this paradox is…

High Energy Physics - Lattice · Physics 2016-05-12 M. Kellerstein , K. Splittorff , J. J. M. Verbaarschot

We investigate the universal features of chiral symmetry breaking in large-$N$ QCD by comparing non-perturbative determinations of the low-lying Dirac spectrum with chiral Random Matrix Theory (RMT) predictions. Our numerical Monte Carlo…

Spontaneous chiral symmetry breaking in QCD with massless quarks at infinite volume can be seen in a finite box by studying, for instance, the dependence of the chiral condensate from the volume and the quark mass. We perform a feasibility…

High Energy Physics - Lattice · Physics 2010-10-27 Leonardo Giusti , Silvia Necco

Partially quenched Quantum Chromodynamics with Wilson fermions on a lattice is considered in the framework of chiral perturbation theory. Two degenerate quark flavours are associated with a chirally twisted mass term. The pion masses and…

High Energy Physics - Lattice · Physics 2010-12-17 Gernot Münster , Christian Schmidt , Enno E. Scholz

These lectures describe the use of effective field theories to extrapolate results from the parameter region where numerical simulations of lattice QCD are possible to the physical parameters (physical quark masses, infinite volume,…

High Energy Physics - Lattice · Physics 2007-05-23 Stephen. R. Sharpe

The microscopic spectral density of the Hermitian Wilson-Dirac operator is computed numerically in quenched lattice QCD. We demonstrate that the results given for fixed index of the Wilson-Dirac operator can be matched by the predictions…

High Energy Physics - Lattice · Physics 2013-05-30 P. H. Damgaard , U. M. Heller , K. Splittorff

We compute fermionic observables relevant to the study of chiral symmetry in quenched QCD using the Overlap-Dirac operator for a wide range of the fermion mass. We use analytical results to disentangle the contribution from exact zero modes…

High Energy Physics - Lattice · Physics 2009-10-31 Robert G. Edwards , Urs M. Heller , Rajamani Narayanan

We extend the epsilon-expansion of continuum chiral perturbation theory to nonzero lattice spacing in the framework of Wilson Chiral Perturbation Theory. We distinguish various regimes by defining the relative power counting of the quark…

High Energy Physics - Lattice · Physics 2010-11-05 Oliver Bar , Silvia Necco , Stefan Schaefer

Close to the continuum the lattice spacing affects the smallest eigenvalues of the Wilson Dirac operator in a very specific manner determined by the way in which the discretization breaks chiral symmetry. These effects can be computed…

High Energy Physics - Lattice · Physics 2012-11-09 K. Splittorff

The electroweak symmetry breaking and origin of masses may be attributed to the breakdown of chiral symmetry due to a strong gauge dynamics. Among several candidates of such gauge systems, we focus on two-color QCD with $N_f=6$ massless…

High Energy Physics - Lattice · Physics 2013-11-06 Masaaki Tomii , Masashi Hayakawa , Ken-Ichi Ishikawa , Shinji Takeda , Norikazu Yamada

Mixed dimensional theories have been used to describe condensed matter systems where fermions are constrained to a plane while the gauge fields they interact with remain four-dimensional. Here we investigate dynamical breaking of chiral…

High Energy Physics - Phenomenology · Physics 2020-09-21 Juan Angel Casimiro Olivares , Luis Albino , Ana Julia Mizher , Alfredo Raya

Most quark actions in lattice QCD encounter difficulties with chiral symmetry and its spontaneous breakdown. Minimally doubled fermions (MDF) are a category of strictly local chiral lattice fermions, whose continuum limit reproduces two…

High Energy Physics - Lattice · Physics 2017-06-23 Johannes Heinrich Weber

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

We present results from quenched spectroscopy calculations with the parametrized fixed-point and the chirally improved Dirac operators. Both these operators are approximate solutions of the Ginsparg-Wilson equation and have good chiral…

In lattice QCD with Wilson fermions, exceptional configurations arise in the quenched approximation at small quark mass. The origin of these large previously uncontrolled lattice artifacts is identified. A simple well-defined procedure…

High Energy Physics - Lattice · Physics 2008-11-26 W. Bardeen , A. Duncan , E. Eichten , G. Hockney , H. Thacker

The classically perfect Fixed-Point fermion action for lattice QCD, a highly improved discretization of the continuum theory that preserves chiral symmetry, is constructed in this thesis and a parallel work by T. Jorg. In the framework of…

High Energy Physics - Lattice · Physics 2007-05-23 Simon Hauswirth

We study chiral symmetry breaking in quenched strong-coupling QED$_4$ in arbitrary covariant gauge within the Dyson-Schwinger equation formalism. A recently developed numerical renormalization program is fully implemented. Results are…

High Energy Physics - Lattice · Physics 2008-11-26 A. G. Williams , F. T. Hawes

We calculate the spectral density of the Dirac operator over an ensemble of configurations composed of overlapping instantons and anti-instantons. We find evidence that the spectral density diverges in the limit of small eigenvalues. This…

High Energy Physics - Lattice · Physics 2009-10-31 U. Sharan , M. Teper

A serious difficulty in conventional lattice field theory calculations is the coupling between the chiral and continuum limits. With both staggered and Wilson fermions, the chiral limit cannot be realized without first taking the limit of…

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