Expectations for Baryon and Lepton Nonconservation

  • Steven Weinberg
Part of the Lie Groups: History, Frontiers and Applications book series (LGR, volume 11)


Are baryon and lepton conservation actually violated in nature? At this moment, we do not know. Nevertheless, it seems a good idea to try to anticipate the details of baryon or lepton nonconserving processes, so that we can at least know what to look for, and what may be learned if it is found. In this talk, I will outline the expected properties of baryon and lepton non-conserving processes, taking as a guide just the strong and electroweak SU(3) × SU(2) × u(l) gauge symmetries and some plausible dimensional analysis. I will also describe a recent calculation of superheavy particle masses, and will have a few comments on the constraints imposed by cosmology on the possible modes of nucleon decay. But before getting into details, I would like to try to set the stage, by describing how our views of baryon and lepton conservation have been shaped by changes in our views about symmetries in general.


Gauge Symmetry Neutrino Mass Lepton Number Renormalization Group Equation Neutrino Mass Matrix 
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Copyright information

© Robert Hermann 1980

Authors and Affiliations

  • Steven Weinberg
    • 1
    • 2
  1. 1.Lyman Laboratory of PhysicsHarvard UniversityUSA
  2. 2.Harvard-Smithsonian Center for AstrophysicsCambridgeUSA

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