On a big desk draped with a whole lot of cables, a maze of mirrors and lenses bounces and guides a skinny beam of laser mild. It culminates at a silvery capsule, which holds 40,000 strontium atoms cooled to inside a whisker of absolute zero. This delicate edifice is an optical clock, one of many world’s most correct timepieces.

Devices like this aren’t precisely designed to be transportable – which makes it greater than a bit of shocking that the operators of 1 such machine on the German nationwide metrology institute packed it right into a trailer and despatched it hurtling down a motorway. It was the beginning of a deadly journey: a nasty jolt might disrupt the beat of its exact ticks. Nevertheless it was obligatory.

That was as a result of, in 2022, scientists globally agreed that we must always begin work on redefining the second based mostly on our newest and best timekeeping expertise: optical clocks. Nonetheless, this meant bringing collectively a number of of the world’s finest specimens for comparability.

Doing so proved an enormous problem, however it is going to certainly be definitely worth the hassle. A brand new definition of the second might be profoundly consequential for almost each different measurement that scientists use to explain nature, from speeds to plenty and extra. Our efforts to outline it extra exactly, then, will ripple out throughout our whole view of the world. “This was the primary world comparability…