The two volumes that comprise String Theory provide an up-to-date, comprehensive account of string theory. Volume 1 provides a thorough introduction to the bosonic string, based on the Polyakov path integral and conformal field theory. The first four chapters introduce the central ideas of string theory, the tools of conformal field theory, the Polyakov path integral, and the covariant quantization of the string. The book then treats string interactions: the general formalism, and detailed treatments of the tree level and one loop amplitudes. Toroidal compactification and many important...

Volume 2: Superstring Theory and Beyond, begins with an introduction to supersymmetric string theories and goes on to a broad presentation of the important advances of recent years. The book first introduces the type I, type II, and heterotic superstring theories and their interactions. It then goes on to present important recent discoveries about strongly coupled strings, beginning with a detailed treatment of D-branes and their dynamics, and covering string duality, M-theory, and black hole entropy, and discusses many classic results in conformal field theory. The final four chapters are...

Volume 2 introduces type I, type II, and heterotic superstring theories and their interactions and presents important discoveries about strongly coupled strings, four-dimensional and other string theories.

This volume is a compilation of lectures delivered at the TASI 2015 summer school, 'New Frontiers in Fields and Strings', held at the University of Colorado Boulder in June 2015. The school focused on topics in theoretical physics of interest to contemporary researchers in quantum field theory and string theory. The lectures are accessible to graduate students in the initial stages of their research careers.