If you are a researcher in theoretical physics with a background in field theory and condensed matter physics, you will find this book a delight. It contains what a good book should offer: the right insight presented by person with taste for relevance...In my opinion, even if one knows the subject, it pays to have a look at the book since one can find the personal touch of people who made major contributions to the subject. -Vladimir Rittenberg Department of Mathematics and Statistics University of Melbourne