Scientists build most accurate atomic clock

A clock, not only to measure time, but gravity as well. It’s impressive that it can measure time dilation due to a height difference of 5mm

Somewhat off-topic:

I’ve often wondered if a hobby-class atomic clock can be built with “a less accurate gas” that is easy to excite and measure in a feedback loop simply because it’s available in a handy package that lends itself for experimentation without having to mess with melting glass and bottles of pressurised gas. E.g. neon, nitrogen or mercury vapour.

The reason I’m asking is because in RF we often need a stable reference, and these come in a clear $ for phase noise relationship: RC, LC, xtal, TCXO, GPSDO, YIG, Rubidium, …

Price-wise, all atomic clocks come after Rubidium. But would it be possible to build an atomic clock that sits between TCXO and Rb both for price and phase noise, by employing a non-exotic gas in a readily available lamp?

Article in Nature https://www.nature.com/articles/s41586-026-11072-8

My back of a envelope maths suggests it's accurate to about 1 second every 300 billion years.

Lutetium-176, element 71, better than 1 part in 10^18.

I mean you think to yourself "one second of error per million years must be quite enough overkill" and then these beautiful people come to show you wrong. I'm not sure who will ever see the difference but really what a job well done!

As long as we don’t go building a glass clock…

Time-servers require hash sigs.

... And still come home late for supper

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