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Related papers: Microscopic Spectrum of the Wilson Dirac Operator

200 papers

Lattice regularization is used to perform chiral perturbation theory calculations in finite volume. The lattice spacing is chosen small enough to be irrelevant, and numerical results are obtained from simple summations.

High Energy Physics - Lattice · Physics 2009-11-10 Bugra Borasoy , Randy Lewis , Daniel Mazur

The spectrum of the Dirac operator near zero virtuality obtained in lattice gauge simulations is known to be universally described by chiral random matrix theory. We address the question of the maximum energy for which this universality…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. E. Berbenni-Bitsch , M. Göckeler , T. Guhr , A. D. Jackson , J. -Z. Ma , S. Meyer , A. Schäfer , H. A. Weidenmüller , T. Wettig , T. Wilke

We compute the scattering amplitude in Wilson Chiral Perturbation Theory for two flavors. The lattice spacing effects due to the explicit chiral symmetry breaking are kept through O(a^2), and we consider the regime where the quark mass m is…

High Energy Physics - Lattice · Physics 2010-01-21 Sinya Aoki , Oliver Bar , Benedikt Biedermann

We have computed ensembles of complete spectra of the staggered Dirac operator using four-dimensional SU(2) gauge fields, both in the quenched approximation and with dynamical fermions. To identify universal features in the Dirac spectrum,…

High Energy Physics - Lattice · Physics 2009-10-31 M. E. Berbenni-Bitsch , M. Göckeler , S. Meyer , A. Schäfer , T. Wettig

Effects of dynamical quarks on the microscopic spectrum of the Wilson Dirac operator are analyzed by means of effective field theory. We consider the distributions of the real modes of the Wilson Dirac operator as well as the spectrum of…

High Energy Physics - Lattice · Physics 2011-07-15 G. Akemann , P. H. Damgaard , K. Splittorff , J. J. M. Verbaarschot

It has been shown recently that Dirac operators satisfying the Ginsparg-Wilson relation provide a solution of the chirality problem in QCD at finite lattice spacing. We discuss different ways to construct these operators and their…

High Energy Physics - Lattice · Physics 2011-07-19 Ferenc Niedermayer

We solve a new chiral Random Two-Matrix Theory by means of biorthogonal polynomials for any matrix size $N$. By deriving the relevant kernels we find explicit formulas for all $(n,k)$-point spectral (mixed or unmixed) correlation functions.…

High Energy Physics - Theory · Physics 2008-11-26 G. Akemann , P. H. Damgaard , J. C. Osborn , K. Splittorff

When chiral symmetry is spontaneously broken, the low-energy part of the Dirac operator spectrum can be computed analytically in the chiral limit. The tool is effective field theory or, equivalently in this case, Random Matrix Theory.

High Energy Physics - Phenomenology · Physics 2007-05-23 P. H. Damgaard

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…

The importance of the spectral density of the Dirac operator in studying spontaneous chiral symmetry breaking and anomalous U(1) axial symmetry breaking are reviewed. It is shown that both types of symmetry breaking can be traced to effects…

Nuclear Theory · Physics 2007-05-23 Thomas D. Cohen

We find the lattice spacing dependence of the eigenvalue density of the non-Hermitian Wilson Dirac operator in the $\epsilon$-domain. The starting point is the joint probability density of the corresponding random matrix theory. In addition…

High Energy Physics - Lattice · Physics 2012-02-09 Mario Kieburg , Jacobus J. M. Verbaarschot , Savvas Zafeiropoulos

In this lecture we review recent lattice QCD studies of the statistical properties of the eigenvalues of the QCD Dirac operator. We find that the fluctuations of the smallest Dirac eigenvalues are described by chiral Random Matrix Theories…

High Energy Physics - Lattice · Physics 2009-10-31 J. J. M. Verbaarschot

We show how the leading physical and Wilson low-energy constants associated with Wilson fermions in lattice gauge theory can be determined individually by using spectral information of the Wilson Dirac operator with fixed index at finite…

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

In these lectures we review recent results on universal fluctuations of QCD Dirac spectra and applications of Random Matrix Theory (RMT) to QCD. We review general properties of Dirac spectra and discuss the relation between chiral symmetry…

High Energy Physics - Theory · Physics 2007-05-23 J. J. M. Verbaarschot

In QCD chiral symmetry is explicitly broken by quark masses, the effect of which can be described reliably by chiral perturbation theory. Effects of explicit chiral symmetry breaking by the lattice regularisation of the Dirac operator,…

High Energy Physics - Lattice · Physics 2011-01-27 Nigel Cundy , Tony Kennedy , Andreas Schäfer

We apply chiral perturbation theory to the pseudoscalar meson mass and decay constant data obtained in the PACS-CS Project toward 2+1 flavor lattice QCD simulations with the O(a)-improved Wilson quarks. We examine the existence of chiral…

In these two lectures given at the 1997 Zakopane workshop on "New Developments in Quantum Field Theory" we review recent results on universal fluctuations in QCD Dirac spectra. We start the first lecture with a review of some general…

High Energy Physics - Theory · Physics 2007-05-23 J. J. M. Verbaarschot

We compute the microscopic spectrum of the QCD Dirac operator in the presence of dynamical fermions in the framework of random-matrix theory for the chiral Gaussian unitary ensemble. We obtain results for the microscopic spectral…

High Energy Physics - Theory · Physics 2009-10-30 T. Wilke , T. Guhr , T. Wettig

In the $\varepsilon$-regime of chiral perturbation theory the spectral correlations of the Euclidean QCD Dirac operator close to the origin can be computed using random matrix theory. To incorporate the effect of temperature, a random…

Mathematical Physics · Physics 2022-01-05 Gernot Akemann , Tim R. Würfel

We derive the microscopic spectral density of the Dirac operator in $SU(N_c\geq 3)$ Yang-Mills theory coupled to $N_f$ fermions in the fundamental representation. An essential technical ingredient is an exact rewriting of this density in…

High Energy Physics - Theory · Physics 2009-10-31 P. H. Damgaard , J. C. Osborn , D. Toublan , J. J. M. Verbaarschot