The widely accepted notion that nothing can exceed the speed of light is not entirely accurate. While Albert Einstein established in 1905 that information cannot travel faster than light, entities without mass or information—such as “darkness”—might surpass this universal speed limit.
An international team of scientists, led by researchers at the Technion Institute of Technology, investigated this concept by examining “dark points” within light waves rather than measuring darkness or the absence of photons directly. These dark points, also called “zero points” or “null points,” are tiny regions where the wave amplitude drops to zero, representing complete darkness embedded within a light field.
These formations, known as vortices, create a phenomenon comparable to a river vortex moving against the current, enabling their speed to be technically superluminal. The study detailing these findings was published in the journal Nature. The authors explained that theory has long predicted optical singularities can exhibit superluminal motion, especially near their moments of creation or annihilation.
In a significant development, the researchers designed a novel microscopy system combining an advanced laser setup with a specialized opto-mechanical component. This allowed them to gather data with exceptional spatial and temporal precision. The experiment involved a thin flake of hexagonal boron nitride, a material that facilitates the conversion of light into “light-sound waves” known as polaritons.
Polaritons are quasiparticles that blend light and matter, drastically reducing the speed of light—by roughly 100 times compared to its velocity in a vacuum. It is within this slowed state that the “dark point” vortices were observed traveling faster than the speed of light, confirming the possibility of superluminal optical darkness.
