"Light from chaos" in two dimensions

Understand

We perform a Monte-Carlo study of the lattice two-dimensional gauged XY-model.

• Our results confirm the strong-coupling expansion arguments that for sufficiently small values of the spin-spin coupling the ``gauge symmetry breaking" terms decouple and the long-distance physics is that of the unbroken pure gauge theory.
• We find no evidence for the existence, conjectured earlier, of massless states near a critical value of the spin-spin coupling.
• We comment on recent remarks in the literature on the use of gauged XY-models in proposed constructions of chiral lattice gauge theories.