This is the softcover reprint of the English translation of Bourbaki's
text Groupes et Algèbres de Lie, Chapters 7 to 9. It completes the
previously published translations of Chapters 1 to 3 (3-540-64242-0) and
4 to 6 (978-3-540-69171-6) by covering the structure and representation
theory of semi-simple Lie algebras and compact Lie groups. Chapter 7
deals with Cartan subalgebras of Lie algebras, regular elements and
conjugacy theorems. Chapter 8 begins with the structure of split
semi-simple Lie algebras and their root systems. It goes on to describe
the finite-dimensional modules for such algebras, including the
character formula of Hermann Weyl. It concludes with the theory of
Chevalley orders. Chapter 9 is devoted to the theory of compact Lie
groups, beginning with a discussion of their maximal tori, root systems
and Weyl groups. It goes on to describe the representation theory of
compact Lie groups, including the application of integration to
establish Weyl's formula in this context. The chapter concludes with a
discussion of the actions of compact Lie groups on manifolds. The nine
chapters together form the most comprehensive text available on the
theory of Lie groups and Lie algebras.