Re: Entangled aluminium ion is world’s best timekeeper – Physics World

[grarpamp]

On 7/13/19, jim bell <jdb10987 at yahoo.com> wrote:
> WWII ... Building
> not demolished until about 1997

Doubt any such non top-secret dusty places made it
past 2000 unravaged by remodelers, various forms of
take-it-home collectors, and renewed searches by
archivists.

>  https://en.wikipedia.org/wiki/Shortt%E2%80%93Synchronome_clock

Though out of sync, the one pictured has 6.5 inHg vac
on it, likely from the draw on the bottom left :)

Here's an earlier generation...

https://en.wikipedia.org/wiki/Riefler_escapement

> Get three clocks, and you
> can begin to do serious work about learning how accurate your knowledge of
> their performance really is.

Yes, lot's of things use comparison schemes... NTP discrimination,
Shuttle guidance computers, nonstop computing, some
filesystems, GPS, etc.

Lots of cool stuff on ebay, especially back during dotbomb
and other thinning cycles.