On Mon, Feb 22, 2010 at 6:50 PM, Daniel Ruoso <dan...@ruoso.com> wrote:
> So why have the duration TAI-based?
> Simply because TAI is supposedly immutable as a scale, so it's predictable.
> Gregorian time is not immutable and timezone definitions are not anyhow
> predictable.

OK, this seems to be a point of confusion.  TAI *is defined in terms
of the Gregorian calendar*.    It is not just a sequence of anonymous
seconds ticking off at the rate specified by SI.   TAI specifies a
name for each second, not just the amount of time between them.  And
that name is a date/time using the Gregorian calendar.  If you like,
you can convert it to a Julian Date, but that's a one-to-one mapping.
You're still going to get a value that's wrong for civil purposes -
that is, currently 34 seconds fast compared to an NTP-synchronized

If Perl's internal idea of time is just a count of atomic seconds,
great.  That, however, is not TAI.  UTC and TAI and the proposed
leap-second-free UTC-replacement "TI" all tick at the same rate and at
the same time, and you can devise any number of time scales that do
likewise, differing only in the labels.

Mark J. Reed <markjr...@gmail.com>

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