Il Nuovo Cimento A (1965-1970)

, Volume 105, Issue 9, pp 1313–1318 | Cite as

Three generations and a large top-quark mass

  • B. F. L. Ward


We interpret the recent discovery by MkII at the SLC that the number of massless neutrino generations is 3 to mean that the family symmetry is indeedSU(3), so that our «low energy» symmetry group isSU(2)L×U1×SU(3) c ×SU(3) f , where low now means small compared to the Planck mass. A possible model with a large top-quark mass is exhibited. The model is made complete by analogy with the originalSU(3)flavor model of Gell-Mann. In fact, if the latter analogy is pursued literally, it leads tomt≅65.8 −8.5 +39.7 GeV. Such a value is currently still viable.


11.15.Ex - Spontaneous breaking of gauge symmetries 


12.15.Cc - Extensions of gauge or Higgs sector 


14.80 - Other and hypothetical particles 


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Copyright information

© Società Italiana di Fisica 1992

Authors and Affiliations

  • B. F. L. Ward
    • 1
  1. 1.Department of Physics and AstronomyUniversity of TennesseeKnoxvilleUSA

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