'This book provides a bridge between two very active and important parts of mathematics and physics, namely the theory of automorphic forms on reductive groups and string theory. The authors have masterfully presented both aspects and their connections, and have provided examples and details at all levels to make the book available to a large readership, including non-experts in both fields. This is a valuable contribution and a welcoming text for graduate students as well.' Freydoon Shahidi, Purdue University, Indiana
'The book is a valuable addition to the literature, and it may inspire more exchange between mathematics and physics at an advanced level.' Anton Deitmar, MathSciNet
'The prerequisites for a profitable reading this book are enormous. Readers without a solid background in algebraic and analytic number theory, classfield theory, modular forms and representation theory will only be able to read a couple of sections. Researchers in these fields will be grateful to the authors and the publisher for providing access to some rather advanced mathematics. The material is presented in a very clear and lucid way; there is an extensive index and a list of references containing 634 items.' Franz Lemmermeyer, zbMATH