The renormalization group running of the three gauge couplings in the Standard Model has been found to nearly, but not quite, meet at the same point if the hypercharge is normalized so that it is consistent with or GUTs, which are precisely the GUT groups which lead to a simple fermion unification.
32.
However, for the left-chirality neutrinos, this term changes weak hypercharge by 2 units-not possible with the standard Higgs interaction, requiring the Higgs field to be extended to include an extra triplet with weak hypercharge 2-whereas for right-chirality neutrinos, no Higgs extensions are necessary.
33.
However, for the left-chirality neutrinos, this term changes weak hypercharge by 2 units-not possible with the standard Higgs interaction, requiring the Higgs field to be extended to include an extra triplet with weak hypercharge 2-whereas for right-chirality neutrinos, no Higgs extensions are necessary.
34.
Beware that folks in the Nuclear Physics crowd use unqualified isospin and hypercharge to refer to the former ones while folks in the High Energy ( Particle Physics ) crowd use those unqualified terms to refer to the latter, which unfortunately adds a lot to the confusion . talk ) 19 : 41, 10 May 2009 ( UTC)
35.
On a similar note, even though the photon is charged under the SU ( 2 ) weak symmetry ( because it is the gauge boson associated with a linear combination of weak isospin and hypercharge ), it is also moving through a condensate of such charges, and so, isn't an exact eigenstate of the weak charges and this theorem doesn't apply either.
36.
:The mass of the strange quark is not entirely negligible but is still small enough that the symmetry operation that replaces the up quark, the down quark and the strange quark among themselves is a " fair " symmetry and the charges associated with that SU ( 3 ) symmetry ( which happen to be the flavor isospin we already talked about plus the flavor hypercharge ) are still somewhat valueable tools.
37.
The 331 model is an extension of the electroweak gauge symmetry from SU ( 2 ) _ W \ times U ( 1 ) _ Y to SU ( 3 ) _ L \ times U ( 1 ) _ X with SU ( 2 ) _ W \ subset SU ( 3 ) _ W and the hypercharge Y = \ beta T _ 8 + I X and the electric charge Q = Y / 2 + T _ 3 / 2 where T 3 and T 8 are the Gell-Mann matrices of SU ( 3 ) L and ? and I are parameters of the model.
