[tz] tzfiles contain Unix epoch for the first transition time

Steve Allen sla at ucolick.org
Sat Aug 15 04:13:10 UTC 2015


On Fri 2015-08-14T20:16:52 -0700, Paul Eggert hath writ:
> $ date -u -r -67767978442512096
> Tue Jan  1 02:38:24 GMT -2147479778
>
> GNU/Linux 'date' is similar except it says 'UTC' rather than 'GMT'
> (of course neither abbreviation is correct for these old time
> stamps).

Of course.

Williams studied tidal rhythmites and found a nearly constant number
of about 410 solar days per year from 2 billion to 1 billion years
before present, which is about 77000 SI seconds in one day.
http://onlinelibrary.wiley.com/doi/10.1029/1999RG900016/abstract

That doesn't work with a calendar that supposes 365.25 days per year.
Any date before human record keeping should decide whether it is
counting seconds, days, or years (and which kind of each) because
using the modern relationships does not correspond to anything.

--
Steve Allen                 <sla at ucolick.org>               WGS-84 (GPS)
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