David Tong: Lectures on String Theory

These lecture notes provide a detailed introduction to the bosonic string and conformal field theory, aimed at "Part III" (i.e. masters level) students. The full set of lectures notes can be downloaded here and weigh in at around 210 pages. Individual sections can be downloaded below.

PDF

Content

• 0. Introduction:   PDF
  Table of Contents; Why study string theory? Aspects of quantum gravity.
• 1. The Classical String:   PDF
  Point Particles, Nambu-Goto Action, Polyakov Action, Weyl Invariance, Mode Expansions.
• 2. The Quantum String:   PDF
  Covariant Quantization; Lightcone Quantization; String Spectrum, Tachyons and Gravitons.
• 3. Open Strings and D-Branes:   PDF
  D-branes; Quantization and a World of Light; Brane Dynamics; Multiple Branes and a World of Glue.
• 4. Introducing Conformal Field Theory:   PDF
  Noether Currents; Operator Product Expansion; Ward Identities; Central Charge, Weyl Anomaly; Radial Quantization; Virasoro Algebra; State-Operator Map.
• 5. Path Integrals and Ghosts:   PDF
  The Path Integral; The Ghost CFT; Critical Dimension; States and Vertex Operators.
• 6. Scattering Amplitudes:   PDF
  What to Compute? The S-matrix; Summing over Topologies; Virasoro-Shapiro Amplitude; Veneziano Amplitude; Moduli Space of the Torus; One-Loop Partition Function; Integrals and Gamma Functions.
• 7. Low Energy Effective Actions:   PDF
  Einstein's Equations, the Beta Function and Ricci Flow; The B-field and the Dilaton; Low Energy Effective Action; Simple Solutions: the String, the Magnetic Brane, the Linear Dilaton; Background Gauge Fields; DBI Action; Yang-Mills.
• 8. Compactification and T-Duality:   PDF
  Kaluza-Klein Compactification; Enhanced Gauge Symmetries; Why Big Circles are the Same as Small Circles.

Problem Sheets

• Problem Sheet 1:   Postscript    PDF    Classical and Quantum Strings


• Problem Sheet 2:   Postscript    PDF    Conformal Field Theory


• Problem Sheet 3:   Postscript    PDF    Mostly Scattering Amplitudes


• Problem Sheet 4:   Postscript    PDF    Background Fields

String Theory on the Web

• Video Lectures on String Theory   by Shiraz Minwalla.


• String Theory   by Angel Uranga.


• Applied Conformal Field Theory   by Paul Ginsparg.


• Sigma Models and String Theory    TASI Lectures by Curt Callan and Lárus Thorlacius.
  (Warning: this link directly downloads a large pdf file of about 45 Mb)


• What is String Theory?    by Joe Polchinski.


• Errata    for Joe Polchinski's String Theory Book.