schwinger_dyson.tex

\left\langle {\psi }\left\mid \mathcal{T}\left\{ \frac{{\delta }}{{\delta }{\phi }} {F}\lbrack {\phi }\rbrack \right\} \right\mid {\psi }\right\rangle =-\mathrm{i}\left\langle {\psi }\left\mid \mathcal{T}\left\{ {F}\lbrack {\phi }\rbrack \frac{{\delta }}{{\delta }{\phi }} {S}\lbrack {\phi }\rbrack \right\} \right\mid {\psi }\right\rangle