[LEAPSECS] drawing the battle lines

[Rob Seaman]

There's a lot of overlap between timekeepers and astronomers.  I'm not sure I embrace the battle metaphor, but if so this would have to be a civil war.

The fundamental issue remains that atomic time and synodic time are two different things.  Thus the BIPM's implicit attempt to divorce the word "day" from its current coherent meaning.

Steve's issues won't go away if UTC is redefined.  Rather confusion would ramify and reify.

Systems, software and society need to characterize dates as coherently as they do times.  Dates and times are for many purposes the same thing (else you wouldn't query them with an atomic system call).  If the BIPM now states otherwise, then what does "day" mean to them?

    "Perfection of means and confusion of goals seem, in my opinion, to characterize our age." - A. Einstein, 28 September 1941

Rob Seaman
National Optical Astronomy Observatory
--

On Mar 20, 2013, at 6:46 AM, Steve Allen <sla at ucolick.org> wrote:


> The BIPM website has a few new tidbits related to UTC.

> 

> They celebrate 25 years since the BIH was abolished, TAI

> was transferred from BIH to BIPM, and Circular T was started.

> 

> They also celebrate one year since starting the new "UTCr".

> 

> And they have published the report of the 19th meeting of the CCTF

> http://www.bipm.org/utils/common/pdf/CCTF19.pdf

> in which there is a long discussion of the UTC shenanigans at ITU-R.

> 

> Concluding the report is Resolution 6 in which the CCTF declares what

> UT1 is and is not, what UTC is, and what a time scale is in a fashion

> that directly contradicts the 1976 IAU definition of time scale.

> 

> In particular, resolution 6 makes it plain that the count of days in a

> calendar and the subdivision of those days is not a time scale if

> those days are measured by astronomical means.  In short, that

> history, tradition, law, and common public perception about what time

> is have been wrong.

> 

> --

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