“Optical-lattice clocks are already the best clocks in the world, and here we get this level of performance that no one has seen before,” remarked Shimon Kolkowitz, a UW-Madison professor and senior author of the study.
“Optical atomic clocks keep time by using a laser that is tuned to match this frequency precisely, and they require some of the world’s most sophisticated lasers to keep accurate time,” the statement added.
"Normally, our laser would limit the performance of these clocks. But because the clocks are in the same environment, and experience the exact same laser light, the effect of the laser drops out completely,” the UW-Madison physicist underlines.
It is “a measurement of precision timekeeping that sets a world record for two spatially separated clocks," the statement added.