The new wave of pilot-wave theory

a) Faraday waves excited above threshold. A millimetric drop b) bounces and c-d) walks over the vibrating bath. Strobed images show e) a walker and f) an orbiting pair.

A decade ago, Yves Couder and Emmanuel Fort discovered that a millimeter-sized droplet may propel itself along the surface of a vibrating fluid bath by virtue of a resonant interaction with its own wave field, and that these walking droplets exhibit several features reminiscent of quantum systems. We here describe the walking-droplet system and, where possible, provide rationale for its quantum-like features. Further, we discuss the physical analogy between this hydrodynamic system and its closest relations in quantum theory, Louis de Broglie’s pilot-wave theory and its modern extensions.

See paper: Bush, Physics Today (2015)