Permutation Symmetry and the Origin of Fermion Mass Hierarchy

Mar, 1990
11 pages
Published in:
  • Phys.Rev.Lett. 64 (1990) 2747
Report number:
  • MdDP-PP-90-158

Citations per year

1990199920082017202402468
Abstract: (APS)
A realization of the ‘‘flavor-democracy’’ approach to quark and lepton masses is provided in the context of the standard model with a horizontal S3 permutation symmetry. In this model, t and b quarks pick up mass at the tree level, c, s-quark and τ-lepton masses arise at the one-loop level, u, d, and μ masses at the two-loop level, and the electron mass at the three-loop level, thus reproducing the observed hierarchial structure without fine tuning of the Yukawa couplings. The pattern of quark mixing angles also emerges naturally, with Vus,Vcb≊O(ε), Vub≊O(ε2), where ε is a loop expansion parameter.
  • gauge field theory: SU(3) x SU(2) x U(1)
  • fermion: flavor
  • fermion: mass
  • mass: fermion
  • hierarchy problem
  • perturbation theory: higher-order
  • symmetry: S(3)
  • quark: mixing angle