Richard Feynman lectures on quantum electrodynamics

Richard Feynman lectures on quantum electrodynamics at the University of Auckland, New Zealand, 1979 have become iconic research materials. 

Thanks to the Vega Science Trust  these lectures are now online for anyone to access. 

Here's a link to Part 2 : Fits of Reflection and Transmission - Quantum Behaviour. What are reflection and transmission, and how do they work?

Source: http://vega.org.uk/video/programme/46