Diffusion of Light (image) University of Zurich Caption This shows the diffusion of light in a disordered, cloudy medium at intervals of one nanosecond (= billionth of a second). After approximately four nanoseconds, the light can no longer spread any further in the medium. Credit University of Zurich Usage Restrictions None Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.