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Related papers: Large N reduction with overlap fermions

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We study quenched QCD just above the phase transition temperature using overlap Fermions. Exact zero modes of the overlap operator are localized. Chiral symmetry is restored, as indicated by the behavior of the chiral condensate after…

High Energy Physics - Lattice · Physics 2015-06-25 R. V. Gavai , Sourendu Gupta , R. Lacaze

We compute Neuberger's overlap operator by the Lanczos algorithm applied to the Wilson-Dirac operator. Locality of the operator for quenched QCD data and its eigenvalue spectrum in an instanton background are studied.

High Energy Physics - Lattice · Physics 2011-07-19 Artan Borici

We derive the vector-like four dimensional overlap Dirac operator starting from a five dimensional Dirac action in the presence of a delta-function space-time defect. The effective operator is obtained by first integrating out all the…

High Energy Physics - Lattice · Physics 2008-11-26 C. D. Fosco , G. Torroba , H. Neuberger

We present results for B_K and selected matrix elements for beyond the standard model interactions obtained in quenched QCD with overlap fermions. We also illustrate results on baryon wave-functions and diquark correlations within baryons…

High Energy Physics - Lattice · Physics 2008-11-26 Ronald Babich , Nicolas Garron , Christian Hoelbling , Joseph Howard , Laurent Lellouch , Claudio Rebbi

The procedure of Dirac reduction of Poisson operators on submanifolds is discussed within a particularly useful special realization of the general Marsden-Ratiu reduction procedure. The Dirac classification of constraints on 'first-class'…

Exactly Solvable and Integrable Systems · Physics 2015-06-26 Krzysztof Marciniak , Maciej Blaszak

Using lattice overlap fermions, we have computed the 1-loop renormalization factors of several operators that measure DIS structure functions and weak amplitudes. Computer codes written in the algebraic manipulation language FORM have been…

High Energy Physics - Lattice · Physics 2007-05-23 Stefano Capitani

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

I present several tricks to help implement the overlap Dirac operator numerically.

High Energy Physics - Lattice · Physics 2015-06-25 H. Neuberger

We construct an $O(a^2)$-improved overlap-Dirac operator by designing an improved overlap kernel, based on the Symanzik improvement program. Field rotation terms are also identified to improve off-shell amplitudes for both massless and…

High Energy Physics - Lattice · Physics 2010-11-05 H. Ikeda , S. Hashimoto

I describe an implementation of the overlap action, which is built from an action which is itself an approximate overlap action. It appears to be about a factor of 15-20 less expensive to use, than the usual overlap action with the Wilson…

High Energy Physics - Lattice · Physics 2008-11-26 Thomas DeGrand

The overlap Dirac operator, which satisfies the Ginsparg-Wilson relation, realizes exact chiral symmetry on the lattice without any unphysical doubler modes. To perform the path integrals, one should, however, note that the overlap fermion…

High Energy Physics - Lattice · Physics 2007-05-23 Hidenori Fukaya

We present non-perturbative renormalization constants of fermionic bilinears on the lattice in the quenched approximation at beta=6.1 using an overlap fermion action with hypercubic(HYP)-blocked links. We consider the effects of the exact…

High Energy Physics - Lattice · Physics 2009-11-11 Thomas DeGrand , Zhaofeng Liu

We compute the one-loop lattice renormalization of the two-quark operators $\bar{\psi} \Gamma \psi$, where $\Gamma$ denotes the generic Dirac matrix, for the lattice formulation of QCD using the overlap-Dirac operator. We also study the…

High Energy Physics - Lattice · Physics 2008-11-26 C. Alexandrou , E. Follana , H. Panagopoulos , E. Vicari

We present results on hadron masses and quark condensate from Neuberger's overlap fermion. The scaling and chiral properties and finite volume effects from this new Dirac operator are studied. We find that the generalized…

High Energy Physics - Lattice · Physics 2015-06-25 K. F. Liu , S. J. Dong , F. X. Lee , J. B. Zhang

Using the overlap-Dirac operator proposed by Neuberger, we have computed in lattice QCD the one-loop renormalization factors of ten operators which measure the lowest two moments of unpolarized and polarized non-singlet quark distributions.…

High Energy Physics - Lattice · Physics 2015-06-25 Stefano Capitani

We calculate $m_{ud}=(m_u+m_d)/2$, $m_s$, $f_\pi$ and $f_K$ in the quenched continuum limit with UV-filtered overlap fermions. We see rather small scaling violations on lattices as coarse as $a^{-1} \simeq 1 \mathrm{GeV}$ and conjecture…

High Energy Physics - Phenomenology · Physics 2009-11-11 Stephan Durr , Christian Hoelbling

I present first results from an in-progress calculation of B_K in quenched approximation using overlap fermions. My particular implementation of the overlap uses a kernel with nearest and next-nearest neighbor interactions and HYP-blocked…

High Energy Physics - Lattice · Physics 2015-06-25 Thomas DeGrand

The overlap fermion offers the considerable advantage of exact chiral symmetry on the lattice, but is numerically intensive. This can be made affordable while still providing large lattice volumes, by using coarse lattice spacing, given…

We present results of lattice computations using overlap fermions on a twisted mass background. $N_f=2$ full QCD gauge configurations have been produced by the ETM Collaboration with very light pions (down to less than 300 MeV), with small…

High Energy Physics - Lattice · Physics 2009-04-14 Nicolas Garron , Luigi Scorzato

In a recent article Hasenfratz and von Allmen have suggested a fixed point action for two flavors of Weyl fermions on the lattice with gauge group SU(2). The block-spin transformation they use maps the chiral and vector symmetries of the…

High Energy Physics - Lattice · Physics 2008-11-26 Christof Gattringer , Markus Pak