Rephasing Invariance and Permutation Symmetry

In the standard model, the permutation symmetry among the three generations of fundamental fermions is usually regarded to be broken by the Higgs couplings. The symmetry may be restored if we include the mass matrix parameters as physical variables which transform appropriately under the symmetry operation. Known relations between these variables, such as the renormalization group equations, as well as formulas for neutrino oscillations (in vacuum and in matter), may be shown to be covariant tensor equations under the permutation symmetry group. On the other hand, with some modifications, the arguments for rephasing invariance may be used to establish permutation symmetry for the standard model.

Project ID:PA10907-1626
External Project ID:MOST109-2112-M182-001