Class Notes for PHY32: String Theory
The Theoretical Minimum Class Series
Professor Leonard Susskind
Origins of string theory in hadron physics, the infinite momentum/boost frame, model of a string
Preliminary math and physics concepts, the model of an open string
Harmonic oscillator review, spin of massless particles (photons and gravitons), the low lying spectrum of strings, tachyon problem, basics of string interactions
Charge quantization (Kaluza-Klein/Dirac Monopole arguments), review of Noether’s theorem, the closed string model, level matching rule
I will be missing this lecture. Covered Planck units, rationale for 26 dimensions in Bosonic string theory. I’ll eventually add notes from video.
Fundamental physics parameters are unit-less, adding spin to mass points of strings, the Veneziano amplitude, and scattering of strings.
Fermionic string oscillations, analytic continuation trick for path integrals, action in string theories, invariance under conformal mapping, applying conformal mapping to string scattering
Some history of path/surface integrals, conformal mapping, use of conformal mapping in string scattering
Gravity and string theory, compactification, the energy spectrum of strings on compact manifolds, T-duality
More on T-duality, D-Branes, modeling QFT, QCD and EM
String theory wrapup, the end of reductionism, S[trength]-duality between D1-strings and fundamental strings, other connections