US government boffins say they have built a clock so precise that it will still be accurate to within one second when life on Earth has ceased.
The "quantum logic clock" will neither gain nor lose a second over the next 3.7 billion years, according to its makers at the US National Institute of Standards and Technology (NIST). It uses a single aluminium atom to keep time, processing its measurements in the same way as experimental quantum computers do - hence the name.
At the moment, the internationally-accepted definition of a second is based on the caesium atom. Thus official time is based on such clocks as the US F1 caesium job, which is wildly inaccurate compared to the new aluminium horology tech at ± 1 second in 100 million years. But according to the NIST inventors, the can of whup-ass opened upon such antique clocks by their latest quantum-logic aluminium kit is of such dimensions as to require action.
"This is a milestone for atomic clocks," says NIST boffin James Chou.
That said, NIST also has other radical new clock prototypes under development in its labs, all contenders to topple caesium from its throne as clock di tutti clocki. Many types of brain-bending science could requires measurements even more precise than Chou and his colleagues' aluminium quantum vibro device.
For ordinary purposes it should be more than accurate enough, however. While the Sun should have some time to run before becoming a red giant - and so engulfing the Earth and much of the solar system - when the aluminium clock has finally wandered off by a second, life on land at least should already have been made extinct as our home star heats up and burns its remaining fuel faster.
Unless we get our skates on in terms of space travel, colonizing other planets etc. in the next couple of billion years, Chou's clock will quite literally be the only one we'll ever need - a veritable doomsday clock.
You can read a draft of Chou and his fellow quantum watchmakers' paper (none blind that we know of) here, in advance of publication in hefty boffinry journal Physical Review Letters. ®