[LEAPSECS] Consensus building?

[Steve Allen]

On Wed 2011-02-02T18:40:43 +0000, Stephen Colebourne hath writ:

> That may all be true. But is the SI second a unit of measurement?


yes, one that can be reproduced a priori anywhere in the universe
that someone has a cesium atom.


> Is it standardised?


yes.


> Those are the only two claims made.


But that's not sufficient for use cases.


> If an SI second is a unit, then it must be possible to have a multiple

> of that unit. Don't read too much into a single statement!


Multiples of a unit imply the likelihood that people will try to
presume linearity.

APIs for computing systems present the ability to handle time scales
at a precision of 1.e-9 or better, yet spacetime itself is not linear
to that level across the span of the earth.

Therefore interpretation of the meaning of multiples requires a huge
conventional conceptual framework.  To get an idea of how large the
framework is just for observers on earth see the 179 pages of the IERS
Conventions 2010
http://www.iers.org/nn_11216/IERS/EN/Publications/TechnicalNotes/tn36.html
and compare those details with previous versions to see the evolution of
the conventional conceptual framework.

In order to agree on what time it is to that level we have to allow
one authority to define that time based on the evolving set of
practices and conventions that experts in the field deem best.  Not
just allow, but as a society recognize the importance of funding their
ongoing efforts, and agree upon the utility of their results.

This requires consensus, something that has been lacking in the ITU-R
process, and fearfully so as seen in the non-consensual forward motion
of the proposal detailed here
http://www.atnf.csiro.au/iau-comm31/activities.php
and also here
http://www.bipm.org/cc/CCTF/Allowed/18/CCTF_09-32_noteUTC.pdf
wherein it almost seems that Ron Beard has some sort of hypnotic
zeal which silences all opposition.


> > Yes, in the sense of human history and culture.

>

> Is it important enough to have two definitions for those two things?


That is the active argument in the ITU-R arena.

--
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