BRST-exact insertions in physical correlation functions
= BRST-exact insertions in physical correlation functions
{c}
{title2=$\langle(s\mathcal O)\prod_iG_i\rangle=0$}
When separated operators $G_i$ are <BRST-closed>, the <graded BRST Ward identity> makes an exact insertion vanish. This is the correlator form of identifying closed representatives that differ by exact terms in <BRST cohomology>. The statement presupposes an invariant measure and suitable boundary conditions.