Coxeter diagram

A labeled graph whose nodes are indexed by the generators of a Coxeter group having (P_i, P_j) as an graph edge labeled by M_(i j) whenever M_(i j)>2, where M_(i j) is an element of the Coxeter matrix. Coxeter-Dynkin diagrams are used to visualize Coxeter groups. A Coxeter-Dynkin diagram is associated with each rational double point, and a Coxeter diagram is sufficient to characterize the algebra of the group.

Coxeter group | Dynkin diagram | rational double point