Dark Phase Singularities Sprint Through Light Without Violating Relativity

Physicists tracked dark points inside a beam of light—optical phase singularities—moving through a wave field at speeds that can exceed light in vacuum. The team used hyperbolic phonon-polaritons in hexagonal boron nitride and ultrafast electron microscopy to observe creation, motion, and annihilation of these vortices in real time, finding that although their velocities appear superluminal, no mass, energy, or information travels faster than light, preserving relativity. The findings provide new tools to map nanoscale dynamics and study topological phenomena across wave systems.