Weak isospin
= Weak isospin
{title2=$T,T^3$}
{wiki}
<Weak isospin> labels representations of the <SU(2)> factor in the electroweak gauge group. A left-handed <lepton> doublet has $T=1/2$ with third-component <eigenvalues> $+1/2,-1/2$; a right-handed charged-<lepton> singlet has $T=0$. Along with <electric charge>, the third component determines the <weak neutral current> through $T^3-Q\sin^2\theta_W$.