Lecture 9 of my Quantum Theory course at McGill University, Fall 2012. Quantum Statistical Mechanics. Density Matrices. Ensembles & Equilibrium States.

The course webpage, including links to other lectures and problem sets, is available at
http://www.physics.mcgill.ca/~maloney...

The written notes for this lecture are available at
http://www.physics.mcgill.ca/~maloney...