On 2022-10-04 16:07, Steve Allen via tz wrote:
A clock that is never reset does not correspond to anything that humans can observe. At no point in history has there been a source of official time that does not experience resets of its clock.
Well, yes, if you take local civil time scales, or UTC, as "official time" -- these times scales are *defined* to have discontinuous steps (eg, at switches between winter and summer time and at leap seconds). So any clock strictly following one of these time scales must have discontinuities. Clocks following continuous time scales (all others: TAI, TCB, TCG, TDT, TT and the various solar times) can stay (and several have stayed in the past) close to these time scales without any discontinuous steps. And the clock on my laptop is even able to follow UTC (less strictly) without experiencing any "resets" (only slight changes in rate). The upcoming redefinition of UTC will stop its discontinuities for at least the next 100 years, so clocks may follow UTC more closely without any resets. Michael Deckers.