Dark scalar doublets and neutrino tribimaximal mixing from A4 symmetry

AbstractIn the context of A4 symmetry, neutrino tribimaximal mixing is achieved through the breaking of A4 to Z3 (Z2) in the charged-lepton (neutrino) sector respectively. The implied vacuum misalignment of the (1,1,1) and (1,0,0) directions in A4 space is a difficult technical problem, and cannot be treated without many auxiliary fields and symmetries (and perhaps extra dimensions). It is pointed out here that an alternative scenario exists with A4 alone and no redundant fields, if neutrino masses are “scotogenic”, i.e. radiatively induced by dark scalar doublets as recently proposed