[LEAPSECS] Consensus building?

[Clive D.W. Feather]

Warner Losh said:

>> SI

>> - the SI-second is a standardised unit of measurement

>> - the SI-second is currently defined as a fixed number of transitions

>> of a caesium atom

>> - the current definition of the SI-second was ratified in 1967

> 

> Agreed.  I'd also add

> - the SI-second forms the basis for many other fundamental units of measure.

> 

>> - an SI-based-minute is formed from exactly 60 SI-seconds

>> - an SI-based-hour is formed from exactly 60 SI-based-minutes and thus

>> exactly 3600 SI-seconds

>> - an SI-based-day is formed from exactly 24 SI-based-hours and thus

>> exactly 86400 SI-seconds

>> 

> These are true only most of the time.  On leap second day, they are all 

> false and off by 1, typically one low.  It all depends on the timescale 

> that you use, and thus there can't be a universal definition here.


Actually, Stephen is right and you're wrong. The BIPM defines an SI minute,
hour, and day in exactly this form. See table 6, page 32, of:
http://www.bipm.org/utils/common/pdf/si_brochure_8_en.pdf

This, of course, implies that "SI-based-" is the same as "TAI-".

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Clive D.W. Feather          | If you lie to the compiler,
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