3 ms·
A cesium stopwatch: https://en.wikipedia.org/wiki/Caesium_standard https://en.wikipedia.org/wiki/Caesium_standard
by saulpw 2y ago
A cesium stopwatch: https://en.wikipedia.org/wiki/Caesium_standard https://en.wikipedia.org/wiki/Caesium_standard
- cobbal 2y agoHow deep in a gravity well are you planning to keep this cesium stopwatch?
- Elucalidavah 2y agoExactly at the point of Null Island at the epoch, of course. Or, in practice, as close an approximation as can be calculated by now.
- defrost 2y agoFun reference, although in that spirit it appears that Null Island at mean sea level for that point might be as much as 22m vertical separation from true 1G Geoid. https://en.wikipedia.org/wiki/Geoid#/media/File:Geoid_undulation_10k_scale.jpg https://en.wikipedia.org/wiki/Geoid#/media/File:Geoid_undula... Approximations are pretty easy until you get into the details, dammit.
- defrost 2y agoNot at all what was asked for; not available as a handheld stopwatch someone could stand with in 1970 ... and I'm doubtful there's such a thing available today. Works if you don't mind a lab bench full of equipment, but doesn't appear to match the specification of the request. Still, thanks for your input.
- wolfendin 2y agoHandheld was never specified directly, just “stood with a” which can just mean “next to.” The HP 5061 was introduced in 1964, why do you think a counter that can reference the frequency standard is not possible? You might want to be more rigorous about reading specifications.
- defrost 2y agoThe HP 5061 is not a handheld stopwatch, at best it's a counter top luggable. > why do you think a counter that can reference the frequency standard is not possible? How on earth did you strawman my thinking to reach that bogus conclusion? You might want to be more rigorous about reading comments and projecting.