My understanding is that QCD has three color charges that are conserved as a result of global SU(3) invariance. What about SU(2) weak? Does it have two types of charges? What I'm getting at is:
U(1) --> 1 type of charge
SU(2) --> ?
SU(3) --> 3 types of charge
Does SU(2) have two types? If not, what is the relation between SU(N) invariance and the number of charge types?
Idea: Maybe both I and I_3 (weak isospin and its third component) are conserved before electroweak symmetry breaking? Is that true? If so, then that would answer my question.