Physicists Observed Optical Vortices That Move Faster Than Light

Researchers recorded optical vortices whose apparent speeds briefly exceeded the vacuum speed of light.

They produced the effect in hexagonal boron nitride, which hosts slow phonon polaritons that form dense vortex patterns.

A high-speed electron microscope captured events over ~3×10^-15 seconds and the team made timelapses by stacking many delayed recordings.