For roughly half a century, the length of one second – assuming you don’t take into account the effects of relativity – has been measured in precisely the same way: by a swinging pendulum. Generations ago, this pendulum hung down from a grandfather clock; nowadays, the most accurate clocks are atomic, but the pendulum concept still holds strong, as these digital boxes are essentially recording the back and forth movements of atoms of cesium.
Now, writing in the journal Optica, a team of researchers has announced that it has designed an atomic clock that uses strontium atoms effectively. With the ability to “tick” faster than cesium, it could form the basis of unprecedentedly accurate timekeeping – one in which only 0.008 nanoseconds are lost each day.
Although almost everyone won’t directly notice the increase in accuracy of humanity’s timekeeping, this clock, if officially adopted as the definer of “one second”, will improve GPS navigation by up to one or two orders of magnitude – say, from 1 meter to 1 centimeter, in certain situations.
Tick tock. Brian A Jackson/Shutterstock
“We want to improve the timekeeping infrastructure all over the world by building better and better clocks and integrating them into the time-keeping infrastructure,” Christian Grebing, a researcher at the Physikalisch-Technische Bundesanstalt in Germany and lead author of the study, said in a statement. “What we demonstrated is a first step towards a global improvement of timekeeping.”