What Feynman could not yet use: the generalised Hong–Ou–Mandel experiment to improve the QED explanation of the Pauli exclusion principle

摘要

In this paper we present a reasoning line for introducing the Pauli exclusion principle in the context of an introductory course on quantum theory based on the sum over paths approach. We start from the argument originally introduced by Feynman in ‘QED: The Strange Theory of Light and Matter’ and improve it by discussing with students modern experimental evidence from the famous Hong–Ou–Mandel experiment with indistinguishable photons and its generalised version using electrons. The experiments can be analysed in a rather simple way using Feynman’s method of ‘arrow multiplication’ for treating processes involving more than one quantum object. The approach described is especially relevant in the formation of high school physics teachers to the basics of modern physics.