Bob wrote:
| Axil I believe electrons have a spin of +1/2, not –1/2. The outgoing
neutrino would have to have
| a –1/2 spin—maybe an electron anti neutrino or whatever its called—a
positron neutrino.
... Sorry for barging into this convo here, but I thought it would be useful to
briefly describe Spin, so we
are all on the same footing...
Spin (or more specifically, intrinsic spin) of electrons are either +1/2 or
–1/2. Remember the Stern-Gerlach
Experiment[1]? ... Electrons (which are Fermions) are spin-1/2 particles,
meaning that they can possess a
spin of +1/2 (Spin Up) or –1/2 (Spin Down), and that they exist in a
superposition of the |+1/2> and |-1/2>
states. The magnitude 1/2 is the value (in units of “h”) of the projection of
the spin along the + or - z axis...
The classical analogue of intrinsic spin, is to envision the electron as a
spherical top that is spinning and
there is a precession around the z axis, at an angle such that the value of the
spin along the z axis is exactly
+/- h/2 ...
... Just as a side note, photons are bosons that have a spin of +/- 1 . You
can break down light (photons) as
a superposition of right and left circularly polarized light; Spin +1 Photons
are termed Right Circularly
Polarized Photons and Spin –1 Photons are the Left Circularly Polarized
Critters[2]...
FYI: You won’t find the term “Critters” in the Wikipedia Notes, sorry!
... Spinless Particles are Particles of Spin 0 ...
... So the spin of the electron<>neutrino pair is a superposition of the
possible spin states...
Carry on!
- Mark Jurich
[1] http://en.wikipedia.org/wiki/Stern%E2%80%93Gerlach_experiment
[2] http://en.wikipedia.org/wiki/Photon_polarization#Angular_momentum_and_spin
