English
Related papers

Related papers: On the spectrum of the QCD Dirac operator

200 papers

Quark spectra in QCD are linked to fundamental properties of the theory including the identification of pions as the Goldstone bosons of spontaneously broken chiral symmetry. The lattice Overlap-Dirac operator provides a nonperturbative,…

High Energy Physics - Theory · Physics 2009-10-31 Robert G. Edwards , Urs M. Heller , Joe Kiskis , Rajamani Narayanan

Large ensembles of complete spectra of the Euclidean Dirac operator for staggered fermions are calculated for SU(2) lattice gauge theory. The accumulation of eigenvalues near zero is analyzed as a signal of chiral symmetry breaking and…

High Energy Physics - Lattice · Physics 2009-10-30 M. E. Berbenni-Bitsch , S. Meyer , A. Schäfer , J. J. M. Verbaarschot , T. Wettig

We review the exact results for microscopic Dirac operator spectra based on either Random Matrix Theory, or, equivalently, chiral Lagrangians. Implications for lattice calculations are discussed.

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

In this talk we review some recent results from random matrix models as applied to some non-perturbative issues in QCD. All of the issues we will discuss touched upon the important phenomenon related to the spontaneous breaking of chiral…

High Energy Physics - Phenomenology · Physics 2007-05-23 Romuald A. Janik , Maciej A. Nowak , Gabor Papp , Ismail Zahed

We derive an analytical expression for the distribution of the k-th smallest Dirac eigenvalue in QCD with imaginary isospin chemical potential in the Dirac operator. Because of its dependence on the pion decay constant F through the…

High Energy Physics - Lattice · Physics 2015-06-03 G. Akemann , A. C. Ipsen

We summarize the analytical solution of the Chiral Perturbation Theory for the Hermitian Wilson Dirac operator of $N_c=2$ QCD with quarks in the fundamental representation. Results have been obtained for the quenched microscopic spectral…

High Energy Physics - Lattice · Physics 2015-05-20 Mario Kieburg , Jacobus Verbaarschot , Savvas Zafeiropoulos

We construct chiral perturbation theory for the gradient flow of the microscopic Dirac eigenvalues and compute the density of and correlations between the microscopic eigenvalues at zero and non-zero flow time. The results show that the…

High Energy Physics - Lattice · Physics 2015-06-22 Alexander S. Christensen , K. Splittorff , J. J. M. Verbaarschot

We compute statistical distributions of individual low-lying eigenvalues of random matrix ensembles interpolating chiral Gaussian symplectic and unitary ensembles. To this aim we use the Nystrom-type discretization of Fredholm Pfaffians and…

High Energy Physics - Lattice · Physics 2015-04-02 Shinsuke M. Nishigaki , Takuya Yamamoto

We compare analytic predictions of non-Hermitian chiral random matrix theory with the complex Dirac operator eigenvalue spectrum of two-colour lattice gauge theory with dynamical fermions at nonzero chemical potential. The Dirac eigenvalues…

High Energy Physics - Lattice · Physics 2009-11-11 G. Akemann , E. Bittner

In this paper we study a random matrix model with the chiral and flavor structure of the QCD Dirac operator and a temperature dependence given by the lowest Matsubara frequency. Using the supersymmetric method for random matrix theory, we…

High Energy Physics - Phenomenology · Physics 2009-10-28 A. D. Jackson , M. K. Şener , J. J. M. Verbaarschot

Macroscopic properties of the strong interaction near its chiral phase transition exhibit scaling behaviors, which are the same as those observed close to the magnetic transition in a 3-dimensional classical spin system with $O(4)$…

High Energy Physics - Lattice · Physics 2023-10-23 Heng-Tong Ding , Wei-Ping Huang , Swagato Mukherjee , Peter Petreczky

We investigate the spectral properties of the Wilson Dirac operator in quenched QCD in the microscopic regime. We distinguish the topological sectors using the index as determined by the Wilson flow method. Consequently, the distributions…

High Energy Physics - Lattice · Physics 2012-01-04 Albert Deuzeman , Urs Wenger , Jair Wuilloud

We use the graded eigenvalue method, a variant of the supersymmetry technique, to compute the universal spectral correlations of the QCD Dirac operator in the presence of massive dynamical quarks. The calculation is done for the chiral…

High Energy Physics - Theory · Physics 2009-10-31 Burkhard Seif , Tilo Wettig , Thomas Guhr

Recently, the Columbia group obtained the valence quark mass dependence of the chiral condensate for lattice QCD simulations with dynamical fermions for a series of couplings close to the critical temperature. In this letter we show that…

High Energy Physics - Phenomenology · Physics 2009-10-28 J. J. M. Verbaarschot

In this chapter of the Oxford Handbook of Random Matrix Theory we introduce chiral Random Matrix Theories with the global symmetries of QCD. In the microscopic domain, these theories reproduce the mass and chemical potential dependence of…

High Energy Physics - Theory · Physics 2009-10-22 J. J. M. Verbaarschot

We investigate the Dirac eigenvalue spectrum ($\rho(\lambda,m_l)$) to study the microscopic origin of axial anomaly in high temperature phase of QCD. We propose novel relations between the derivatives ($\partial^n \rho(\lambda,m_l)/\partial…

High Energy Physics - Lattice · Physics 2021-12-08 Heng-Tong Ding , Sheng-Tai Li , Swagato Mukherjee , Akio Tomiya , Xiao-Dan Wang , Yu Zhang

At low temperature in the epsilon regime of QCD the low-end of the Dirac spectrum is described by random matrix theory. In contrast, there has been no similarly well established staistical description in the high temperature, chirally…

High Energy Physics - Lattice · Physics 2010-11-16 Tamas G. Kovacs , Ferenc Pittler

We compute by Monte Carlo methods the individual distributions of the $k$th smallest Dirac operator eigenvalues in QCD, and compare them with recent analytical predictions. We do this for both massless and massive quarks in an SU(3) gauge…

High Energy Physics - Lattice · Physics 2009-10-31 P. H. Damgaard , U. M. Heller , R. Niclasen , K. Rummukainen

We evaluate level spacing and smallest eigenvalue distributions of chiral random matrix ensembles transiting from symplectic or orthogonal to unitary symmetry classes with a crossover parameter rho. As expected from the effective sigma…

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

We compare eigenvalue correlations of the Dirac operator with a chemical potential obtained from lattice simulations of quenched QCD with analytic predictions obtained from chiral effective theories in the zero-momentum limit. By comparing…

High Energy Physics - Lattice · Physics 2008-11-26 James C. Osborn , Tilo Wettig