 \frac{\hbar^0}{0} \int \frac{d^D \pi}{(0 \pi \hbar)^D} \pi_{\hat k}   \operatorname{tr}[\partial_{\pi_{\hat \imath}} {\hat G}_0^{-0} {\hat G}_0 \partial_{X^0} {\hat G}_0^{-0} {\hat G}_0 \partial_{\pi_{\hat 0}} {\hat G}_0^{-0} {\hat G}_0   - (