Coxeter and Dynkin Diagrams

Coxeter and Dynkin Diagrams Posted by John Baez Dynkin diagrams have always fascinated me. They are magically potent language — you can do so much with them! Here’s my gentle and expository intro to Dynkin diagrams and their close relative, Coxeter diagrams: Abstract. Coxeter and Dynkin diagrams classify a wide variety of structures, most notably finite reflection groups, lattices having such groups as symmetries, compact simple Lie groups and complex simple Lie algebras. The simply laced or...