Spontaneous violation of CP symmetry in the strong interactions.
Some time ago Dashen [Phys. Rev. D 3, 1879 (1971)] pointed out that spontaneous CP violation can occur in the strong interactions. I show how a simple effective Lagrangian exposes the remarkably large domain of quark mass parameters for which this occurs. I close with some warnings for lattice simulations.
Creutz
Michael
M
Physics Department, Brookhaven National Laboratory, Upton, New York 11973, USA.