Georgi's Harvard lectures (he's taught physics there since 1980) discuss application of the theory of Lie Algebras and their representations to a wide variety of problems in particles physics and quantum mechanics. This edition has been expanded to include more extensive discussion of finite group theory and representations of the permutation group, as well as discussion of new subjects such as Dynkin indices, spontaneous symmetry breaking, lepton number as a fourth color, and the 27-dimensional representation of E(6). Annotation c. Book News, Inc., Portland, OR (booknews.com)