Colloquium Natural and Life Sciences - Gabriel Dufour

Identical microscopic particles (electrons, atoms, …) are fundamentally indistinguishable. As a result, our mathematical description of a many-particle system must be invariant under the exchange of any two identical particles. This symmetry has important consequences for the dynamics of such systems and is at the root of the many-particle interference phenomenon. I will present the Hong-Ou-Mandel effect as an example of such interference for two particles, where the result of the experiment depends crucially on whether the particles can be distinguished. I will then extend this line of thought to the realm of many interacting particles evolving continuously in a network of coupled sites—as can be realized experimentally with cold atoms—and show how the dynamics is affected when the distinguishability of the participating particles is varied.