Double-slit experiment

The pilot episode opens as Sheldon is discussing a famous physics experiment called ‘The Double-Slit Experiment’. This experiment demonstrates the fact that light behaves as both particles and as waves. More information: http://en.wikipedia.org/wiki/Double-slit_experiment. There’s also an excellent video explanation here: http://www.youtube.com/watch?v=DfPeprQ7oGc.