English
Related papers

Related papers: Improved Overlap Fermions

200 papers

We study the 2-flavor lattice Schwinger model with Wilson fermions in the chiral limit. The quark mass is determined using the PCAC definition. We numerically compute the masses of the iso-triplet (pi) and iso-singlet particles (eta) for…

High Energy Physics - Lattice · Physics 2009-10-31 Christof Gattringer , Ivan Hip , C. B. Lang

The chiral Schwinger model is formulated in the wilson-fermion formulation on the lattice and then simulated by the complex langevin algorithm. The simulation is done both without and with gauge fixing to the Lorentz gauge for the compact…

High Energy Physics - Lattice · Physics 2009-10-28 T. D. Kieu , P. S. Hawkins

We present first results of classical-statistical real-time simulations of anomalous transport phenomena with overlap fermions. We find that even on small lattices overlap fermions reproduce the real-time anomaly equation with much better…

High Energy Physics - Lattice · Physics 2016-12-15 P. V. Buividovich , S. N. Valgushev

Fermionic theories with a vanishing chiral condensate (in the chiral limit) have recently attracted considerable interest; in particular variants of multi-flavour QCD are candidates for this behaviour. Here we consider the 2-flavour…

High Energy Physics - Lattice · Physics 2020-07-14 Wolfgang Bietenholz , Ivan Hip , David Landa-Marbán

We present first results from a simulation of quenched overlap fermions with improved gauge field action. Among the quantities we study are the spectral properties of the overlap operator, the chiral condensate and topological charge, quark…

High Energy Physics - Lattice · Physics 2008-11-26 D. Galletly , M. Gürtler , R. Horsley , B. Joo , A. D. Kennedy , H. Perlt , B. J. Pendleton , P. E. L. Rakow , G. Schierholz , A. Schiller , T. Streuer

I review the physics of lattice fermions obeying the Ginsparg-Wilson relation. I describe their relation to domain wall fermions. I give a description of methodology for performing numerical simulations with overlap fermions. This is a…

High Energy Physics - Lattice · Physics 2026-03-06 Thomas DeGrand

We present simulation results employing overlap fermions for the axial correlation functions in the epsilon-regime of chiral perturbation theory. In this regime, finite size effects and topology play a dominant role. Their description by…

High Energy Physics - Lattice · Physics 2009-11-10 W. Bietenholz , T. Chiarappa , K. Jansen , K. -I. Nagai , S. Shcheredin

A certain U(1) model in 2 dimensions, describing four right handed unit charged Weyl fermions interacting with one doubly charged left handed Weyl fermion, is exactly soluble and has massless Majorana-Weyl composites. Instanton induced…

High Energy Physics - Lattice · Physics 2009-10-30 Yoshio Kikukawa , Herbert Neuberger

We present a set of related Hybrid Monte Carlo methods to simulate an arbitrary number of dynamical overlap fermions. Each fermion is represented by a chiral pseudo-fermion field. The new algorithm reduces critical slowing down in the…

High Energy Physics - Lattice · Physics 2009-11-11 Thomas DeGrand , Stefan Schaefer

We present simulation results obtained with overlap hypercube fermions in QCD near the chiral limit. We relate our results to chiral perturbation theory in both, the epsilon-regime and in the p-regime. In particular we measured the pion…

High Energy Physics - Lattice · Physics 2009-11-11 W. Bietenholz , S. Shcheredin

Considering Ginsparg-Wilson type fermions dynamically in lattice QCD simulations is a challenging task. The hope is to be able to approach smaller pion masses and to eventually reach physical situations. The price to pay is substantially…

High Energy Physics - Lattice · Physics 2009-11-11 C. B. Lang , Pushan Majumdar , Wolfgang Ortner

The vacuum overlap formalism is extended to describe the supersymmetric multiplet of a Weyl fermion, a complex scalar boson and an auxiliary field in the case without interaction, based on the fact that supersymmetry can be maintained upto…

High Energy Physics - Lattice · Physics 2016-08-25 Tatsumi Aoyama , Yoshio Kikukawa

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

In this letter we show that the overlap formulation of chiral gauge theories correctly reproduces the gravitational Lorentz anomaly in 2-dimensions. This formulation has been recently suggested as a solution to the fermion doubling problem…

High Energy Physics - Theory · Physics 2009-12-30 S. Randjbar-Daemi , J. Strathdee

We carry out a comparative study among five-dimensional formulations of chirally symmetric fermions about the algorithmic performance, chiral symmetry violation and topological tunneling to find a computationally inexpensive formulation…

High Energy Physics - Lattice · Physics 2013-11-28 The JLQCD Collaboration , T. Kaneko , S. Aoki , G. Cossu , H. Fukaya , S. Hashimoto , J. Noaki

We study the 2-flavour lattice Schwinger model: QED in D=2 with two fermion species of identical mass. In the simulation we are using Wilson fermions where chiral symmetry is explicitly broken. Since there is no known simple order parameter…

High Energy Physics - Lattice · Physics 2009-10-30 I. Hip , C. B. Lang , R. Teppner

We describe a conceptually simple, but important test for the overlap approach to the construction of lattice chiral gauge theories. We explain the equivalence of the overlap formula with a certain waveguide model for a simple set of gauge…

High Energy Physics - Lattice · Physics 2009-10-28 Maarten Golterman , Yigal Shamir

It is shown that the Ginsparg-Wilson relation implies an exact symmetry of the fermion action, which may be regarded as a lattice form of an infinitesimal chiral rotation. Using this result it is straightforward to construct lattice Yukawa…

High Energy Physics - Lattice · Physics 2009-10-31 Martin Lüscher

Three aspects of symmetry structure of lattice chiral fermion in the overlap formalism are discussed. By the weak coupling expansion of the overlap Dirac operator, the axial anomaly associated to the chiral transformation proposed by…

High Energy Physics - Lattice · Physics 2009-10-31 Y. Kikukawa

The properties of the quark propagator in Landau gauge in quenched QCD are examined for the overlap quark action. The overlap quark action satisfies the Ginsparg-Wilson relation and as such provides an exact lattice realization of chiral…

High Energy Physics - Lattice · Physics 2016-08-16 Frédéric D. R. Bonnet , Patrick O. Bowman , Derek B. Leinweber , Anthony G. Williams , J. B. Zhang