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In quantum chromodynamics with static quarks the confinement-deconfinement phase transition is connected to the spontaneous breaking of the global Z3 center symmetry. This symmetry is lost when one considers dynamical quarks. Owing to the fractional electric charge of quarks, we recover a global Z6 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.
Above the pseudocritical temperature T_c of chiral symmetry restoration a chiral spin symmetry (a symmetry of the color charge and of electric confinement) emerges in QCD. This implies that QCD is in a confining mode and there are no free quarks. At
In this work, we first use Thompsons renormalization group method to treat QCD-vacuum behavior close to the regime of asymptotic freedom. QCD-vacuum behaves effectively like a paramagnetic system of a classical theory in the sense that virtual color
A natural explanation of confinement can be given in terms of symmetry. Since color symmetry is exact, the candidate symmetry is dual and related to homotopy,i.e., in (3+1)d, to magnetic charge conservation. A set of r abelian tHooft-like tensors (r
We report a comprehensive analysis of the light and strange disconnected-sea quarks contribution to the nucleon magnetic moment, charge radius, and the electric and magnetic form factors. The lattice QCD calculation includes ensembles across several
We present SU(3) gluon propagators calculated on 48*48*48*N_t lattices at beta=6.8 where N_t=64 (corresponding the confinement phase) and N_t=16 (deconfinement) with the bare gauge parameter,alpha, set to be 0.1. In order to avoid Gribov copies, we e