Time-Based Double-Slit Experiment Reveals Light's Interference with Its Own Past.

Physicists at Imperial College London have recreated the famous double-slit experiment using time instead of space. They fired light through a material that changes its properties in femtoseconds, only allowing light to pass through at specific times in quick succession. The interference patterns showed up as changes in the frequency or color of the beams of light, demonstrating wave-particle duality. The experiment has helped in understanding materials that can minutely control the behavior of light in space and time, with potential applications in signal processing and light-powered computers.