Kerodon

\begin{equation} \begin{gathered}\label{equation:balanced-coupling-family-over-edge2} \xymatrix@R =50pt@C=50pt{ \widetilde{\operatorname{\mathcal{E}}}_0 \ar [r]^-{ \widetilde{F} } \ar [d]^{ \lambda _0 } & \widetilde{\operatorname{\mathcal{E}}}_1 \ar [d]^{ \lambda _1} \\ \operatorname{\mathcal{E}}_0^{\vee } \times \operatorname{\mathcal{E}}_0 \ar [r]^-{ F^{\vee } \times F} & \operatorname{\mathcal{E}}_1^{\vee } \times \operatorname{\mathcal{E}}_1 } \end{gathered} \end{equation}