Quantum Mechanics 11 - De Broglie Waves Are Complex

Recording Details

Speaker(s): 
Collection/Series: 
PIRSA Number: 
08080086

Abstract

The de Broglie waves we have been using thus far were assumed to be real functions; we discuss why this is wrong and how to fix the problem.

Learning Outcomes:

• Understanding why there is a serious flaw with using real de Broglie waves, and how using a complex wave (one with both a real and an imaginary part) solves the problem.

• Understanding how the de Broglie wave corresponding to a free particle is like a moving corkscrew, with a magnitude that is uniform across space and constant in time.

• When right- and left-travelling de Broglie waves (“corkscrews”) are added, as happens for a particle in a box, we get a complex standing wave whose magnitude is constant in time.