🚀 go-pugleaf

vijay@wiliki.eng.hawaii.edu (Vijay Fafat) writes...
> Suppose the neutrino HAS a non-zero mass and suppose I see a left-handed
> neutrino going.  I decide to overtake it... do I get a LIGHT right-handed
> neutrino?

If you give the neutrino a Majorana mass (as is done in the usual see-saw
mechanism), then when you overtake the light left-handed neutrino you will
see a light right-handed antineutrino!  The see-saw theory also contains a
heavy right-handed neutrino and its antiparticle, a heavy left-handed
antineutrino, but these do not appear in your "experiment".

The trick here is that Majorana masses violate any quantum number which the
particle carries (here, e.g., lepton number), so "particle" and
"antiparticle" are not as well-distinguished as we normally imagine.  If
the electron had a Majorana mass (instead of a Dirac mass), lepton number
and electric charge would be violated.

P.S. Sorry for the quadruple post earlier.  My posting software was acting
up; I wasn't trying to prove my claims by repeated assertion!

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