Here on Earth, it might not matter if your wristwatch runs a few seconds slow. But crucial spacecraft functions need accuracy down to one billionth of a second or less. Navigating with GPS, for ...

For decades, physicists have pursued a goal that sounds nearly impossible: to build a clock that keeps time using an atom's nucleus rather than the electrons orbiting it. "Having worked in this field ...

Vladan Vuletić with members of his Experimental Atomic Physics group. From left to right: Matthew Radzihovsky, Leon Zaporski, Qi Liu, Vladan Vuletić, and Gustavo Velez. Every time you check the time ...