Nothing in life is perfect, and after four months many readers have been kind enough to point out a number of typos and errors. These are available in either gzipped postscript or pdf format.

Many thanks to the following for their careful reading of the book:

Mikko Nieminen
Greg Grunberg
George Craig
Anthony Garratt
Alison Brennan
Manuel Berondo
Norbert Nemec
Paul Leopardi
Eric Chisolm
Hyo-Kun Hahn
Robert Lasenby

Further thanks to Greg and Anthony for their suggestions of improvements to the text. I have not included these in the errata, but many of the suggestions will be implemented in later editions.