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Related papers: Gapless Dirac Spectrum at High Temperature

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We study symmetry breaking and gap generation for fermions in the 2D space of constant negative curvature (the Lobachevsky plane) in an external covariantly constant magnetic field in a four-fermion model. It is shown that due to the…

High Energy Physics - Phenomenology · Physics 2008-11-26 E. V. Gorbar , V. P. Gusynin

We study the restoration of the spontaneously broken chiral symmetry and the anomalously broken axial U(1) symmetry in finite temperature QCD at zero chemical potential. We use 2 flavors lattice QCD with optimal domain-wall fermion on the $…

High Energy Physics - Lattice · Physics 2013-12-02 Ting-Wai Chiu , Wen-Ping Chen , Yu-Chih Chen , Han-Yi Chou , Tung-Han Hsieh

Dynamical nature of the gauge degree of freedom and its effect to fermion spectrum are studied for four-dimensional nonabelian chiral gauge theory in the vacuum overlap formulation. The covariant gauge fixing term and the Faddeev-Popov…

High Energy Physics - Lattice · Physics 2007-05-23 Yoshio Kikukawa

We present a detailed study of the interplay between chiral symmetry and spectral properties of the Dirac operator in lattice gauge theories. We consider, in the framework of the Schwinger model, the fixed point action and a fermion action…

High Energy Physics - Lattice · Physics 2009-10-31 F. Farchioni , I. Hip , C. B. Lang , M. Wohlgenannt

Overlap fermions are particularly well suited to study the finite temperature dynamics of the chiral symmetry restoration transition of QCD, which might be just an analytic crossover. Using gauge field configurations on a 24^3x10 lattice…

High Energy Physics - Lattice · Physics 2008-11-26 V. Weinberg , E. -M. Ilgenfritz , K. Koller , Y. Koma , Y. Nakamura , G. Schierholz , T. Streuer

Real-time anomalous fermion number violation is investigated for massless chiral fermions in spherically symmetric SU(2) Yang-Mills gauge field backgrounds which can be weakly dissipative or even nondissipative. Restricting consideration to…

High Energy Physics - Theory · Physics 2009-11-07 F. R. Klinkhamer , Y. J. Lee

We study two well-known $SU(N)$ chiral gauge theories with fermions in the symmetric, anti-symmetric and fundamental representations. We give a detailed description of the global symmetry, including various discrete quotients. Recent work…

High Energy Physics - Theory · Physics 2022-01-11 Philip Boyle Smith , Avner Karasik , Nakarin Lohitsiri , David Tong

We investigate the eigenvalue spectrum of the staggered Dirac matrix in SU(3) gauge theory and in full QCD as well as in quenched U(1) theory on various lattice sizes. As a measure of the fluctuation properties of the eigenvalues, we study…

High Energy Physics - Lattice · Physics 2007-05-23 Bernd A. Berg , Harald Markum , Rainer Pullirsch , Tilo Wettig

We construct a new order parameter for finite temperature QCD by considering the quark condensate for U(1)-valued temporal boundary conditions for the fermions. Fourier transformation with respect to the boundary condition defines the dual…

High Energy Physics - Lattice · Physics 2008-11-26 Erek Bilgici , Falk Bruckmann , Christof Gattringer , Christian Hagen

The Thirring model is an interacting fermion theory with current-current interaction. The model in $1+2$ dimensions has applications in condensed-matter physics to describe the electronic excitations of Dirac materials. Earlier…

High Energy Physics - Lattice · Physics 2019-09-11 Julian Lenz , Björn Wellegehausen , Andreas Wipf

In this work we investigate the infrared behaviour of a Yang-Mills theory coupled to a massless fermion in the adjoint representation of the gauge group SU(2). This model has many interesting properties, corresponding to the $\mathcal{N}=2$…

High Energy Physics - Lattice · Physics 2022-12-07 Georg Bergner , Juan Camilo Lopez , Stefano Piemonte , Ivan Soler Calero

We demonstrate that chiral symmetry restoration in quenched finite temperature QCD depends crucially on the $Z_3$ phase of the Polyakov loop ${\cal P}$. This dependence is a general consequence of the coupling of the chiral order parameter…

High Energy Physics - Lattice · Physics 2011-05-05 Peter N. Meisinger , Michael C. Ogilvie

We investigate the properties of quarks and gluons above the chiral phase transition temperature $T_c,$ using the RG improved gauge action and the Wilson quark action with two degenerate quarks mainly on a $32^3\times 16$ lattice. In the…

High Energy Physics - Lattice · Physics 2016-08-24 K. -I. Ishikawa , Y. Iwasaki , Yu Nakayama , T. Yoshie

We discuss the excitation spectra around the Dirac node on a surface of a three-dimensional topological insulator. By using the diagrammatic expansion, we show that the coupling of an electron with the gauge field in the presence of…

Mesoscale and Nanoscale Physics · Physics 2013-05-09 Tetsuro Habe , Yasuhiro Asano

We consider the simulation of finite temperature QCD with two flavors of dynamical overlap fermions in order to study the suppression of the axial U(1) symmetry breaking at the chiral phase transition point. As a preliminary study, pure…

High Energy Physics - Lattice · Physics 2012-04-23 Guido Cossu , Sinya Aoki , Shoji Hashimoto , Takashi Kaneko , Hideo Matsufuru , Jun-ichi Noaki , Eigo Shintani

We present our recent studies of the pseudo-critical temperature, $T_c$, of QCD using domain wall fermions. Domain wall fermions have the advantage that they preserve exact SU(2) chiral symmetry at finite lattice spacing in the limit that…

High Energy Physics - Lattice · Physics 2010-01-21 Michael Cheng

We analyze the vacuum structure of SU(2) QCD with multiple massless adjoint representation fermions formulated on a small spatial $S^1 \times \R^3$. The absence of thermal fluctuations, and the fact that quantum fluctuations favoring the…

High Energy Physics - Theory · Physics 2008-11-26 Mithat Unsal

We evaluate the chiral condensate and Polyakov loop in two-dimensional QED with a fermion of an arbitrary mass ($m$). We find discontinuous $m$ dependence in the chiral condensate and anomalous temperature dependence in Polyakov loops when…

High Energy Physics - Theory · Physics 2009-10-30 Yutaka Hosotani , Ramon Rodriguez

In this lecture we argue that the fluctuations of Dirac eigenvalues on the finest scale, i.e. on the scale of the average level spacing do not depend on the underlying dynamics and can be obtained from a chiral random matrix theory with the…

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

We investigate the effect of a uniform background magnetic field on the chiral symmetry breaking in SU(2) Yang-Mills theory on the lattice. We observe that the chiral condensate grows linearly with the field strength B up to \sqrt{e B} = 3…

High Energy Physics - Lattice · Physics 2009-12-14 P. V. Buividovich , M. N. Chernodub , E. V. Luschevskaya , M. I. Polikarpov