Fractional Charge and Confinement of Quarks
Philipp Scior, Sam O. Edwards, Lorenz von Smekal · Proceedings of 31st International Symposium on Lattice Field Theory LATTICE 2013 — PoS(LATTICE 2013) · 2014
In quantum chromodynamics with static quarks the confinement-deconfinement phase transition is connected to the spontaneous breaking of the global Z 3 center symmetry.This symmetry is lost when one considers dynamical quarks.Owing to the fractional electric charge of quarks, we recover a global Z 6 center symmetry when QCD is regarded as a part of the Standard Model.We present results from QCD-like theories extended by electromagnetic interactions and show that the weak coupling limit of the QED part of the model results in a center-like symmetry with disorder in the vacuum.This can be seen explicitly in a character expansion of the fermion determinant.Further, we show that corresponding center averages project the fermion determinant on N-ality zero and discuss whether the additional center symmetry can be used to eliminate the fermion sign problem in QCD with fundamental quarks.