Lecture
This lecture covers the construction of irreducible Coxeter groups, focusing on the classical groups A_n, B_n, and D_n. The slides discuss Dunkin diagrams for Weyl groups, the relationship between long and short roots, and the geometric equivalence of Coxeter graphs. The lecture also explores the simply laced groups An, Dn, E6, E7, and Ez. It concludes with the generation of reflections and the crystallographic conditions for Coxeter groups.