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Vacuum alignment and lattice artifacts: Wilson fermions

Confinement in asymptotically free gauge theories is accompanied by the spontaneous breaking of the global flavor symmetry. If a subgroup of the flavor symmetry group is coupled weakly to additional gauge fields, the vacuum state tends to align such that the gauged subgroup is unbroken. Independently, a lattice discretization of the continuum theory typically reduces the manifest flavor symmetry, and, in addition, can give rise to new lattice-artifact phases with spontaneously broken symmetries. Here, we study the interplay of these two phenomena for Wilson fermions, using chiral lagrangian techniques. We consider two examples: electromagnetic corrections to QCD, and a prototype composite-Higgs model.