Neutrino–antineutrino mass splitting in the Standard Model and baryogenesis

On the basis of a previously proposed mechanism of neutrino–antineutrino mass splitting in the Standard Model, which is Lorentz and SU(2)×U(1)SU(2)×U(1) invariant but non-local to evade the CPT   theorem, we discuss the possible implications of neutrino–antineutrino mass splitting on neutrino physics and baryogenesis. It is shown that non-locality within a distance scale of the Planck length, that may not be fatal to unitarity in a generic effective theory, can generate the neutrino–antineutrino mass splitting of the order of the observed neutrino mass differences, which is tested in oscillation experiments, and a non-negligible baryon asymmetry depending on the estimate of sphaleron dynamics. The one-loop order induced electron–positron mass splitting in the Standard Model is shown to be finite and estimated at ∼10−20 eV∼10−20 eV, well below the experimental bound <10−2 eV<10−2 eV. The induced CPT violation in the K  -meson in the Standard Model is expected to be even smaller and well below the experimental bound |mK−mK¯|<0.44×10−18 GeV.