Higgs Parity, strong CP and dark matter

An exact spacetime parity replicates the SU(2) x U(1) electroweak interaction, the Higgs boson H, and the matter of the Standard Model. This Higgs Parity and the mirror electroweak symmetry are spontaneously broken at scale v '=< H '>>>< H >, yielding the Standard Model below v ' with a quartic coupling that essentially vanishes at v ': lambda(SM)(v ') similar to 10(-3). The strong CP problem is solved as Higgs parity forces the masses of mirror quarks and ordinary quarks to have opposite phases. Dark matter is composed of mirror electrons, e ', stabilized by unbroken mirror electromagnetism. These interact with Standard Model particles via kinetic mixing between the photon and the mirror photon, which arises at four-loop level and is a firm prediction of the theory. Physics below v ', including the mass and interaction of e ' dark matter, is described by one fewer parameter than in the Standard Model. The allowed range of me ' is determined by uncertainties in (alpha(s), m(t), m(h)), so that future precision measurements of these will be correlated with the direct detection rate of e ' dark matter, which, together with the neutron electric dipole moment, will probe the entire parameter space.