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Related papers: Random Matrix Models for Dirac Operators at finite…

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A unified classification and analysis is presented of two dimensional Dirac operators of QCD-like theories in the continuum as well as in a naive lattice discretization. Thereby we consider the quenched theory in the strong coupling limit.…

High Energy Physics - Lattice · Physics 2013-10-28 Mario Kieburg , Jacobus J. M. Verbaarschot , Savvas Zafeiropoulos

We describe a way to optimize the chiral behavior of Wilson-type lattice fermion actions by studying the low energy real eigenmodes of the Dirac operator. We find a candidate action, the clover action with fat links with a tuned clover…

High Energy Physics - Lattice · Physics 2007-05-23 Thomas DeGrand , Anna Hasenfratz , Tamás G. Kovács

We provide first evidence that Matrix Models describe the low lying complex Dirac eigenvalues in a theory with dynamical fermions at non-zero density. Lattice data for gauge group SU(2) with staggered fermions are compared to detailed…

High Energy Physics - Lattice · Physics 2007-05-23 Gernot Akemann , Elmar Bittner

We study cutoff effects at tree-level of perturbation theory for standard Wilson and Wilson twisted mass fermionic lattice actions with Nf=2 flavour degenerate quarks. The discretization effects are investigated by computing the mass…

High Energy Physics - Lattice · Physics 2009-04-14 K. Cichy , J. Gonzalez Lopez , K. Jansen , A. Kujawa , A. Shindler

It was established that distribution of the near-zero modes of the Dirac operator is consistent with the Chiral Random Matrix Theory (CRMT) and can be considered as a consequence of spontaneous breaking of chiral symmetry (SBCS) in QCD. The…

High Energy Physics - Lattice · Physics 2018-04-18 M. Catillo , L. Ya. Glozman

We compute the chiral condensate in 2+1-flavor QCD through the spectrum of low-lying eigenmodes of Dirac operator. The number of eigenvalues of the Dirac operator is evaluated using a stochastic method with an eigenvalue filtering technique…

High Energy Physics - Lattice · Physics 2016-08-22 Guido Cossu , Hidenori Fukaya , Shoji Hashimoto , Takashi Kaneko , Jun-Ichi Noaki

We review the application of random matrix theory (RMT) to chiral symmetry in QCD. Starting from the general philosophy of RMT we introduce a chiral random matrix model with the global symmetries of QCD. Exact results are obtained for…

High Energy Physics - Lattice · Physics 2016-09-01 J. J. M. Verbaarschot

Some consequences which follow from the periodicity assumption for spectral density of Wilson--Dirac operator are studied. Such an assumption allows to obtain simple representations for quark propagator, which reveals an important role of…

High Energy Physics - Lattice · Physics 2007-05-23 Vladimir K. Petrov

The low-lying eigenvalues of a (sparse) hermitian matrix can be computed with controlled numerical errors by a conjugate gradient (CG) method. This CG algorithm is accelerated by alternating it with exact diagonalisations in the subspace…

High Energy Physics - Lattice · Physics 2008-11-26 Thomas Kalkreuter , Hubert Simma

We have calculated complete spectra of the staggered Dirac operator on the lattice in quenched SU(3) gauge theory for \beta = 5.4 and various lattice sizes. The microscopic spectral density, the distribution of the smallest eigenvalue, and…

High Energy Physics - Lattice · Physics 2008-11-26 M. Göckeler , H. Hehl , P. E. L. Rakow , A. Schäfer , T. Wettig

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 measure the low lying eigenmodes of an overlap Dirac operator on 2--flavor staggered configurations. By comparing the eigenmode distribution to the predictions of Random Matrix Theory we test to what accuracy staggered configurations…

High Energy Physics - Lattice · Physics 2008-11-26 Anna Hasenfratz , Roland Hoffmann

We consider the effect of a non-zero lattice spacing on the low-energy effective theory of Wilson fermions with one flavor. Analytical results are given for both the chiral condensate and the microscopic spectral density of the Wilson Dirac…

High Energy Physics - Theory · Physics 2015-05-30 Rasmus Normann Larsen

The microscopic spectral eigenvalue correlations of QCD Dirac operators in the presence of dynamical fermions are calculated within the framework of Random Matrix Theory (RMT). Our approach treats the low--energy correlation functions of…

High Energy Physics - Lattice · Physics 2008-11-26 G. Akemann , E. Kanzieper

We investigate the distribution of the spacings of adjacent eigenvalues of the lattice Dirac operator. At zero chemical potential $\mu$, the nearest-neighbor spacing distribution $P(s)$ follows the Wigner surmise of random matrix theory…

High Energy Physics - Lattice · Physics 2009-10-31 H. Markum , R. Pullirsch , K. Rabitsch , T. Wettig

We propose a lattice model for Dirac fermions which allows us to break the degeneracy of the node structure. In the presence of a random gap we analyze the scaling behavior of the localization length as a function of the system width within…

Disordered Systems and Neural Networks · Physics 2014-12-23 A. Hill , K. Ziegler

We investigate the eigenvalues of nearly chiral lattice Dirac operators constructed with five-dimensional implementations. Allowing small violation of the Ginsparg-Wilson relation, the HMC simulation is made much faster while the…

High Energy Physics - Lattice · Physics 2013-11-20 H. Fukaya , S. Aoki , G. Cossu , S. Hashimoto , T. Kaneko , J. Noaki

We study discretization effects in a mixed-action lattice theory with domain-wall valence quarks and Asqtad-improved staggered sea quarks. At the level of the chiral effective Lagrangian, discretization effects in the mixed-action theory…

High Energy Physics - Lattice · Physics 2008-11-26 C. Aubin , Jack Laiho , Ruth S. Van de Water

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

As a feasibility study for a scaling test we investigate the behavior of algorithms for dynamical fermions in the N_f=2 Schroedinger functional at an intermediate volume of 1 fm^4. Simulations were performed using HMC with two…

High Energy Physics - Lattice · Physics 2009-11-10 Michele Della Morte , Roland Hoffmann , Francesco Knechtli , Ulli Wolff