TY - JOUR

T1 - Chiral symmetry breaking in nearly conformal gauge theories

AU - Fodor, Zoltán

AU - Holland, Kieran

AU - Kuti, Julius

AU - Nógrádi, Dániel

AU - Schroeder, Chris

N1 - Funding Information:
We are thankful to Claude Bernard and Steve Sharpe for help with staggered perturbation theory and to Ferenc Niedermayer for discussions on rotator dynamics. We are grateful to Sandor Katz and Kalman Szabo for the Wuppertal RHMC code, and for some calculations, we used the publicly available MILC code. We performed simulations on the Wuppertal GPU cluster, Fermilab clusters under the auspices of USQCD and SciDAC, and the Ranger cluster of the Teragrid organization. This work is supported by the NSF under grant 0704171, by the DOE under grants DOE-FG03-97ER40546, DOE-FG-02-97ER25308, by the DFG under grant FO 502/1 and by SFB-TR/55.
Publisher Copyright:
© Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike Licence.

PY - 2009

Y1 - 2009

N2 - We present new results on chiral symmetry breaking in nearly conformal gauge theories with fermions in the fundamental representation of the SU(3) color gauge group. The number of fermion flavors is varied in an extended range below the conformal window with chiral symmetry breaking (cSB) for all flavors between Nf = 4 and Nf = 12. To identify cSB we apply several methods which include, within the framework of chiral perturbation theory, the analysis of the Goldstone spectrum in the p-regime and the spectrum of the fermion Dirac operator with eigenvalue distributions of random matrix theory in the e-regime. Chiral condensate enhancement is observed with increasing Nf when the electroweak symmetry breaking scale F is held fixed in technicolor language. Important finite-volume consistency checks from the theoretical understanding of the SU(Nf ) rotator spectrum of the d-regime are discussed. We also consider these gauge theories at Nf = 16 inside the conformal window. The importance of understanding finite volume, zero momentum gauge field dynamics inside the conformal window is pointed out. Staggered lattice fermions with supressed taste breaking are used throughout the simulations.

AB - We present new results on chiral symmetry breaking in nearly conformal gauge theories with fermions in the fundamental representation of the SU(3) color gauge group. The number of fermion flavors is varied in an extended range below the conformal window with chiral symmetry breaking (cSB) for all flavors between Nf = 4 and Nf = 12. To identify cSB we apply several methods which include, within the framework of chiral perturbation theory, the analysis of the Goldstone spectrum in the p-regime and the spectrum of the fermion Dirac operator with eigenvalue distributions of random matrix theory in the e-regime. Chiral condensate enhancement is observed with increasing Nf when the electroweak symmetry breaking scale F is held fixed in technicolor language. Important finite-volume consistency checks from the theoretical understanding of the SU(Nf ) rotator spectrum of the d-regime are discussed. We also consider these gauge theories at Nf = 16 inside the conformal window. The importance of understanding finite volume, zero momentum gauge field dynamics inside the conformal window is pointed out. Staggered lattice fermions with supressed taste breaking are used throughout the simulations.

UR - http://www.scopus.com/inward/record.url?scp=85055284611&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85055284611&partnerID=8YFLogxK

M3 - Conference article

AN - SCOPUS:85055284611

SN - 1824-8039

VL - 91

JO - Proceedings of Science

JF - Proceedings of Science

T2 - 27th International Symposium on Lattice Field Theory, LAT 2009

Y2 - 26 July 2009 through 31 July 2009

ER -