Watching the clock (IMAGE) University of Colorado at Boulder Caption Graduate students Theo Lukin Yelin, left, and Alec Cao, right, monitor an optical atomic clock via computer. Credit Patrick Campbell/CU Boulder Usage Restrictions Use with credit only License Original 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.