Smectics Image (IMAGE) Cornell University Caption The key to understanding smectics is the analogy to Einstein's relativity. If we view 'time' as the number of layers crossed (plotted upward) by a pulse of light at the centers of the concentric circles, then equally spaced layers correspond to a constant speed of light - leading to 'light cones' at a constant angle. Credit Cornell University, James Sethna Lab Usage Restrictions None License Licensed content 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.