Given \(X\in {\mathsf{Sch}}_{/S}\), define the diagonal morphism as \(\Delta_{X/S}: X\to X \underset{\scriptscriptstyle {S} }{\times} X\):
Given \(X\in {\mathsf{Sch}}_{/S}\), define the diagonal morphism as \(\Delta_{X/S}: X\to X \underset{\scriptscriptstyle {S} }{\times} X\):