nanog mailing list archives
Re: F-ckin Leap Seconds, how do they work?
From: Vadim Antonov <avg () kotovnik com>
Date: Tue, 03 Jul 2012 16:02:29 -0700
On 7/3/2012 2:35 PM, Tony Finch wrote:
Peter Lothberg <roll () Stupi SE> wrote:As the definition of a atomic second is 9192631770 complete oscillations of cesium 133 between enery level 3 and 4, "everyone" can make a second in their lab, that's TAI.No, TAI isn't based on the SI second you realise in your lab. It's the SI second realised on the geoid by a large fleet of clocks.
I think if anyone here is well aware of that that's be Peter:)The reason for the fleet of clocks is partly political, partly practical (cesium clocks are not the most precise... so averaging between a bunch of them is used to calibrate better master clocks). But in theory, if you can get the technical wrinkles worked out, you can derive the same frequency standard in your lab with a single instrument.
(One more issue is that non-relativistic time is not only the frequency of oscillators, but also a reference point).
--vadim
Current thread:
- Re: F-ckin Leap Seconds, how do they work?, (continued)
- Re: F-ckin Leap Seconds, how do they work? Steven Bellovin (Jul 02)
- Re: F-ckin Leap Seconds, how do they work? Jimmy Hess (Jul 02)
- Re: F-ckin Leap Seconds, how do they work? Joly MacFie (Jul 02)
- Re: F-ckin Leap Seconds, how do they work? Tony Finch (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Wolfgang S. Rupprecht (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Owen DeLong (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Jay Ashworth (Jul 03)
- RE: F-ckin Leap Seconds, how do they work? Keith Medcalf (Jul 03)
- RE: F-ckin Leap Seconds, how do they work? Peter Lothberg (Jul 03)
- RE: F-ckin Leap Seconds, how do they work? Tony Finch (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Vadim Antonov (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Tony Finch (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Vadim Antonov (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Steve Allen (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Vadim Antonov (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Christopher Morrow (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Jimmy Hess (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Peter Lothberg (Jul 05)
- Re: F-ckin Leap Seconds, how do they work? Jay Ashworth (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Owen DeLong (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Steve Allen (Jul 03)