Topology, symmetry, and phase transitions in lattice gauge ... - tuprints

5.3 explorations in a 2-color world 103
Figure 5.5: Volume averaged SU(2) Polyakov loop on 4 × 16 3 lattices, in the pure gauge theory
(green), 2-color QCD with κ = 0.15 Wilson quarks (red), and the SU(2)×U(1)
toy model with fractionally charged quarks. The electromagnetic coupling β em
here is varied from total U(1) disorder, β em = 0, to deep in the Coulomb phases,
β em = 2.
0.8
0.6
〈|P2α|〉
0.4
0.2
0
0 0.5 1 1.5 2
β em
β col = 2.3
Figure 5.6: (left) Volume averaged U(1) Polyakov loop corresponding to integer charged
particles, on the 4 × 16 3 ensembles as in Fig. 5.5 for β col = 2.3, in the presence of
fractionally charged Wilson quarks with κ = 0.15. Here we see the ordering of
the U(1) links e i2α µ(x) for integer charges as ones crosses into the Coulomb phase
β em ≥ 1. (right) Depiction of the qualitative difference across the transition for
the U(1) angles that appear in the parallel transporters for quarks. The U(1)
gauge coupling β em is unable to remove a Z 2 phase.