Foreword
Preface
Notation
1 A first look at strings
1.1 Why strings?
1.2 Action principles
1.3 The open string spectrum
1.4 Closed and unoriented strings
Exercises
2 Conformal field theory
2.1 Massless scalars in two dimensions
2.2 The operator product expansion
2.3 Ward identities and Noether's theorem
2.4 Conformal invariance
2.5 Free CFTs
2.6 The Virasoro algebra
2.7 Mode expansions
2.8 Vertex operators
2.9 More on states and operators
Exercises
3 The Polyakov path integral
3.1 Sums over world-sheets
3.2 The Polyakov path integral
3.3 Gauge fixing
3.4 The Weyl anomaly
3.5 Scattering amplitudes
3.6 Vertex operators
3.7 Strings in curved spacetime
Exercises
4 The string spectrum
4.1 Old covariant quantization
4.2 BRST quantization
4.3 BRST quantization of the string
4.4 The no-ghost theorem
Exercises
5 The string S-matrix
5.1 The circle and the torus
5.2 Moduli and Riemann surfaces
5.3 The measure for moduli
5.4 More about the measure
Exercises
6 Tree-level amplitudes
6.1 Riemann surfaces
6.2 Scalar expectation values
6.3 The bc CFT
6.4 The Veneziano amplitude
6.5 Chan-Paton factors and gauge interactions
6.6 Closed string tree amplitudes
6.7 General results
Exercises
