Dear all, I have never commented on this topic, I do it now with a proposal.
- The leap second takes into account a sort of 'noise', unpredictable
before, for small variations in the speed of the Earth's rotation.
Anyway, over the millennia this speed will decrease, so the leap second
is not enough but the 'physical' second will deviate from the
'astronomical' one.
The physical one is necessary to measure the astronomical one and they
are two different things despite the attempts of recent centuries to
make them equivalent
- Martian days have a different second, residents will use the physical
second as unit of measurement for their scientific instrument but they
will want to live a 24-hour day (in any case full hours) with an
astronomical second significantly different from the physical one.
- At the end of the 18th century the meter was calibrated as 1/10000 of
the distance between the equator and the pole, it was later found that
the measurement is a few kilometers more and also changes from one
meridian to another, not to mention the equator.
This did not change the unit of measurement and did not impose a wrong
measurement of the Earth. It is accepted that the meter has an
autonomous definition distinct from the geographic measurements of the
planet.
In my opinion the problem is in the name: the 'second' is a name that
derives from a fraction of the day while the physical second is a unit
of measurement that is still unnamed.
If the physical second had a definition, it would help put an end once
and for all between the demands of scientific measurement and the rhythm
of a planet's days.
The gnomonists are the most focused community on the history of time for
which I am launching a proposal:
help the scientific world to find a definition for the physical second,
giving it a separate identity from the local astronomical second (Earth,
Mars, etc.).
This forum could be the place to put forward some shared proposal and
start using it.
It does not matter if the scientific community wants to change it, it
would still be a success to have established that the physical second
has a different name and identity from our dear old terrestrial second.
That of clocks and sundials, and of our terrestrial life.
Long live the second, ciao Fabio
Il 21/11/2022 17:39, Steve Lelievre ha scritto:
Ah, the joys of Listservs and email software. My participation
sometimes gets of of step too: occasionally, original posts reach me
after other people's replies.
Perhaps it wouldn't be a problem if all the world's computers were
exactly synchronized... perhaps they could use atomic clocks for that
;-)
Cheers,
Steve
On 2022-11-21 12:04 a.m., John Pickard wrote:
Sorry Steve,
I sent my post before seeing yours.
--
Cheers, John.
Dr John Pickard.
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--
Fabio Savian
[email protected]
www.nonvedolora.eu
Paderno Dugnano, Milano, Italy
45° 34' 9'' N, 9° 9' 54'' E, UTC +1 (DST +2)
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