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Spontaneous violation of CP symmetry in the strong interactions

Michael Creutz
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Abstract

Some time ago Dashen 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.

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Michael Creutz. 2004-03-28. Spontaneous violation of CP symmetry in the strong interactions. https://doi.org/10.1103/physrevlett.92.201601

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