String Theory and M-Theory

String Theory and M-Theory (Fall 2010, Stanford Univ.). In this set of lectures Professor Leonard Susskind gives an introduction to String Theory, which he describes as a mathematical framework for theories that unify all the forces of nature, including gravity. In string theory, fundamental objects are no longer point particles; instead they are strings or higher dimensional objects called D-branes. These objects also require additional ingredients such as extra spatial dimensions. (from

Lecture 01 - The historical origins of string theory
The historical origins of string theory, Mesons as quarks connected by strings (gluon tubes), The infinite momentum frame, also known as the light cone frame, The Hamiltonian of a string.
Lecture 02 - Mathematics of string motion
Dirichlet and Neumann boundary conditions, Fourier series, The open string, The energy levels (excitations) of a string.
Lecture 03 - The energy spectrum of strings
This lecture develops an algebraic approach to the energy spectrum of strings. Raising and lowering operators are associated with the modes of the strings. The lecture finishes with the basics of string interactions.
Lecture 04 - Closed strings and the level matching rule
Why is charge quantized? Noether’s theorem and conserved charges, A model of closed strings, The energy spectrum of closed strings, The level matching rule.
Lecture 05 - Bosonic strings
Examining the ground state of bosonic strings, Planck units, The introduction of additional dimensions in which the string can vibrate or stretch.
Lecture 06 - String with spin
String mass points with spin, A review of particle scattering, Meson scattering and the Veneziano amplitude -- string like, String scattering concepts.
Lecture 07 - Fermionic strings and path integrals
The ground state of Fermionic strings, The action for a string, Path integral review, Path integrals in string theory lead to the Laplace equation.
Lecture 08 - Conformal mapping and string scattering
Conformal maps and analytic functions, Analytic functions produce conformal maps, Linear fractional mapping, String scattering concepts.
Lecture 09 - Strings in compact dimensions
Strings moving on a sphere, Periodic dimensions, Quantizing string motion on a torus, The duality of winding and quantized momentum - T-duality.
Lecture 10 - T-duality, D-branes and modeling field theories
Leonard Susskind continues his discussion on T-Duality; explains the theory of D-Branes; models QFT and QCD; and introduces the application of electromagnetism.
Lecture 11 - String theory wrapup
The theory of reductionism, The end of reductionism, Geometric gymnastics with strings and D-branes.

String Theory (Fall, 2010) | The Theoretical Minimum
In this set of lectures Professor Susskind gives an introduction to String Theory, which he describes as a mathematical framework for theories that unify all the forces of nature, including gravity.

The Theoretical Minimum Courses
Classical Mechanics (Fall 2007)
Classical Mechanics (Fall 2011)
Quantum Mechanics (Winter 2008)
Quantum Mechanics (Winter 2012)
Advanced Quantum Mechanics (Fall 2013)
Special Relativity (Spring 2008)
Special Relativity (Spring 2012)
Einstein's General Theory of Relativity (Fall 2008)
General Relativity (Fall 2012)
Cosmology (Winter 2009)
Cosmology (Winter 2013)
Statistical Mechanics (Spring 2009)
Statistical Mechanics (Spring 2013)
Particle Physics 1: Basic Concepts (Fall 2009)
Particle Physics 2: Standard Model (Spring 2010)
Particle Physics 3: Supersymmetry and Grand Unification (Spring 2010)
String Theory and M-Theory (Fall 2010)
Topics in String Theory (Cosmology and Black Holes) (Winter 2011)
Quantum Entanglements, Part 1 (Fall 2006)
Relativity (Spring 2007)