Higgs Parity, strong CP and dark matter

A bstract An exact spacetime parity replicates the SU(2) × 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 ′: λ SM ( v ′) ∼ 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 m_e m e ′ is determined by uncertainties in ( α 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.