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Related papers: Microscopic universality with dynamical fermions

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We introduce Random Matrix Models for the Hermitian Wilson-Dirac operator of QCD-like theories. We show that they are equivalent to the $\epsilon$-limit of the chiral Lagrangian for Wilson chiral perturbation theory. Results are obtained…

High Energy Physics - Lattice · Physics 2013-03-14 Mario Kieburg , Jacobus J. M. Verbaarschot , Savvas Zafeiropoulos

We compute individual distributions of low-lying eigenvalues of a chiral random matrix ensemble interpolating symplectic and unitary symmetry classes by the Nystr\"om-type method of evaluating the Fredholm Pfaffian and resolvents of the…

High Energy Physics - Lattice · Physics 2018-02-20 Takuya Yamamoto , Shinsuke M. Nishigaki

We analyze the eigenvalue statistics of the staggered Dirac operator above $T_{c}$ in QCD with 2+1 flavors of dynamical quarks. We use physical quark masses in our simulations. We compare the eigenvalue statistics from several parts of the…

High Energy Physics - Lattice · Physics 2011-11-16 Tamás G. Kovács , Ferenc Pittler

Recently, Kalkreuter obtained complete Dirac spectra for $SU(2)$ lattice gauge theory both for staggered fermions and for Wilson fermions. The lattice size was as large as $12^4$. We performed a statistical analysis of these data and found…

High Energy Physics - Lattice · Physics 2008-11-26 M. A. Halasz , T. Kalkreuter , J. J. M. Verbaarschot

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

In this lecture we give a brief review of chiral Random Matrix Theory (chRMT) and its applications to QCD at nonzero chemical potential. We present both analytical arguments involving chiral perturbation theory and numerical evidence from…

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

We simulate $ SU(2) $ lattice gauge theory using dynamical reduced staggered fermions. The latter lead to two rather than four Dirac fermions in the continuum limit. We review the derivation and properties of reduced staggered fermions and…

High Energy Physics - Lattice · Physics 2019-01-23 Simon Catterall , Nouman Butt

We analyze Dirac spectra of two-dimensional QCD like theories both in the continuum and on the lattice and classify them according to random matrix theories sharing the same global symmetries. The classification is different from QCD in…

High Energy Physics - Lattice · Physics 2014-10-22 Mario Kieburg , Jacobus J. M. Verbaarschot , Savvas Zafeiropoulos

We analyze how individual eigenvalues of the QCD Dirac operator at nonzero quark chemical potential are distributed in the complex plane. Exact and approximate analytical results for both quenched and unquenched distributions are derived…

High Energy Physics - Lattice · Physics 2008-11-26 G. Akemann , J. Bloch , L. Shifrin , T. Wettig

It is well-known that staggered fermions do not necessarily satisfy the same global symmetries as the continuum theory. We analyze the mechanism behind this phenomenon for arbitrary dimension and gauge group representation. For this purpose…

High Energy Physics - Lattice · Physics 2018-07-31 Mario Kieburg , Tim R. Würfel

We construct a random matrix model that, in the large $N$ limit, reduces to the low energy limit of the QCD partition function put forward by Leutwyler and Smilga. This equivalence holds for an arbitrary number of flavors and any value of…

High Energy Physics - Theory · Physics 2016-09-06 E. V. Shuryak , J. J. M. Verbaarschot

Recent results from the UKQCD Collaboration's dynamical simulations are presented. The main feature of these ensembles is that they have a fixed lattice spacing and volume, but varying sea quark mass from infinite (corresponding to the…

High Energy Physics - Lattice · Physics 2009-11-07 Chris Allton

Starting from the chiral Lagrangian for Wilson fermions at nonzero lattice spacing we have obtained compact expressions for all spectral correlation functions of the Hermitian Wilson Dirac operator in the $\epsilon$-domain of QCD with…

High Energy Physics - Lattice · Physics 2011-12-05 K. Splittorff , J. J. M. Verbaarschot

We study various improved staggered quark Dirac operators on quenched gluon backgrounds in lattice QCD generated using a Symanzik-improved gluon action. We find a clear separation of the spectrum into would-be zero modes and others. The…

High Energy Physics - Lattice · Physics 2008-11-26 E. Follana , A. Hart , C. T. H. Davies

Motivated by the statistical fluctuation of Dirac spectrum of QCD-like theories subjected to (pseudo)reality-violating perturbations and in the epsilon-regime, we compute the smallest eigenvalue distribution and the level spacing…

High Energy Physics - Lattice · Physics 2013-12-18 Shinsuke M. Nishigaki

We confront exact analytical predictions for the finite-volume scaling of the chiral condensate with data from quenched lattice gauge theory simulations. Using staggered fermions in both the fundamental and adjoint representations, and…

High Energy Physics - Lattice · Physics 2009-10-31 P. H. Damgaard , R. G. Edwards , U. M. Heller , R. Narayanan

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

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 show that the lowest part of the eigenvalue density of the staggered fermion operator in lattice QCD_3 at small lattice coupling constant beta has exactly the same shape as in QCD_4. This observation is quite surprising, since universal…

High Energy Physics - Lattice · Physics 2011-02-28 P. Bialas , Z. Burda , B. Petersson

We investigate the spectrum of the staggered Dirac operator in 4d quenched U(1) lattice gauge theory and its relationship to random matrix theory. In the confined as well as in the Coulomb phase the nearest-neighbor spacing distribution of…

High Energy Physics - Lattice · Physics 2015-06-25 Bernd A. Berg , Harald Markum , Rainer Pullirsch , Tilo Wettig