The Fundamental Group
In this chapter, we will look more closely at the fundamental group of a compact Lie group G. We will show that it is a finitely generated Abelian group and that each loop in G can be deformed into any given maximal torus. Then we will show how to calculate the fundamental group. Along the way we will encounter another important Coxeter group, the affine Weyl group. The key arguments in this chapter are topological and are adapted from Adams .
KeywordsFundamental Group Maximal Torus Bruhat Decomposition Affine Weyl Group Simple Positive Root