Am Do., 13. Okt. 2022 um 17:31 Uhr schrieb John Cowan <xxxxxx@ccil.org>:
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> On Thu, Oct 13, 2022 at 2:40 AM Marc Nieper-Wißkirchen <xxxxxx@gmail.com> wrote:
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>> What do you mean by "tai-epoch-time", by the way?
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> 1958-01-01T00:00:00 UTC (which is the point at which UTC-TAI is zero).
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> By the way, it turns out that not all TAI seconds are the same length, per WIkipedia:
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> In the 1970s, it became clear that the clocks participating in TAI were ticking at different rates due to gravitational time dilation, and the combined TAI scale, therefore, corresponded to an average of the altitudes of the various clocks. Starting from the Julian Date 2443144.5 (1 January 1977 00:00:00), corrections were applied to the output of all participating clocks, so that TAI would correspond to proper time at the geoid (mean sea level). Because the clocks were, on average, well above sea level, this meant that TAI slowed by about one part in a trillion.
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> However, I think we can ignore this discrepancy.

Or, we simply make Julian Date 2443144.5 the fixed epoch being
returned by (epoch-time). From then on, proper time (of the reference
frame of Earth's geoid) and TAI time correspond.

>> Would it make sense to define a jiffy as a nanosecond for
>> implementations of the large language?
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> That works for me.

https://codeberg.org/scheme/r7rs/issues/97

PS: What kind of second does SRFI 19's time difference store by the way?