SU(4)XU(1) GAUGE-THEORY .2. CP NON-CONSERVATION

We exploit the higher symmetry inherent in an SU(4) × U(1) gauge theory to construct a spontaneously broken theory of CP nonconservation. Higgs multiplets in the adjoint representation of SU(4) contain both even and odd CP fields; thus, requiring the simultaneous nonvanishing of the vacuum expectation values of these fields leads to CP noninvariance of the vacuum. We find that all the CP-nonconserving effects are mediated in our theory by the superheavy gauge bosons of the broken SU(4) × U(1) symmetry. In fact, the very existence of CP violation sets an upper limit on the masses of these bosons. In our model the dominant CP effect lies in the neutral kaon system and is found to arise through a direct (ΔS=2) K1-K2 transition. The model has all the features of a superweak theory, with a neutron electric dipole moment substantially smaller than 10-24 e cm. © 1979 The American Physical Society.