User:Hippoking

$$\mathrm{Trace}(T^{\mu\nu})=\mathrm{Trace}(T_\mu^{.\nu}) = \mathrm{Trace}(F_{\mu\alpha}F^{\alpha\nu})+\frac{1}{4}\mathrm{Trace}(\eta_\mu^{.\nu} F_{\alpha\beta}F^{\alpha\beta})$$