"Imagine a wristwatch that wouldn't lose a second, even if it ran for billions of years." This captivating vision, expressed by physicist Jun Ye, encapsulates the groundbreaking advancements in time measurement.
In a collaborative effort spanning Finland, France, Germany, Italy, the United Kingdom, and Japan, scientists have made significant strides toward redefining the second, the fundamental unit of time. This international goal could be realized within this decade. The research involved the simultaneous analysis of ten optical clocks over 45 days.
Optical clocks, which are up to 100 times more accurate than the current standard, cesium clocks, are at the heart of this endeavor. The experiment, conducted under the European ROCIT project, utilized a combination of fiber optic cables and satellite connections, a key differentiator from previous studies. This approach provided essential information on what still needs to be done for optical clocks to achieve the reliability needed for use in international time scales.
The infrastructure connected different laboratories across thousands of kilometers in Europe. A total of 38 simultaneous frequency ratios were obtained, four of which were unprecedented. The others were measured with a higher level of precision than previously achieved. This leap in precision could revolutionize how we measure time, with implications ranging from meteorology to studies of the fundamental physics of the universe.
The adoption of these devices could benefit not only the global synchronization of systems but also enable more precise tests of the theory of relativity and investigations into phenomena like dark matter. The scientific community is optimistic about these advancements.
Meanwhile, other promising technologies are also in development. Among them are nuclear clocks, which measure the vibration not of an entire atom but of an atomic nucleus. According to the U.S. National Institute of Standards and Technology (NIST), a prototype of this type of clock is in an advanced stage. This research brings us closer to this level of precision.