Chiral scalar spinor overlap
= Chiral scalar spinor overlap
{title2=$\bar u_Ru_L=m_{\rm spinor}$}
A <Lorentz scalar> Dirac bilinear connects opposite chiralities. In the stated on-shell normalization $\bar u_Ru_L=m_{\rm spinor}$, whereas $\bar u_Lu_L=0$. Such an overlap verifies the allowed Lorentz structure but does not determine an independent coefficient multiplying a different <mass> operator.