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Comment by creatonez | Hacker News Reader

Sure, but political timezones shifted by more than 12 hours 65,000 years in the future seems like the sort of thing that would really screw up our existing code. (I wonder what happens if you put such an entry in tzdata right now? Maybe we should put Null Island at +37:00 or something crazy like +1000:00 to start hardening now)

And maybe we should stop touching political timezones by then anyways.

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In less than half a century, we've created 3 different time standards (TAI, GPS, and now UTC) that tick identically and differ only by arbitrary constant offsets (+37, +18 and +0 seconds). If we haven't come up with an elegant solution by then it's likely 65000 years from now most computing power will be spent running time-conversion libraries.

Time zones change all the time, often on amazingly short notice.

Random local government people declare it is to be, and ... as an industry we largely figure it out.

The more responsible governments give amble notice and as an industry we are very very good at that (you not realizing it, is an example).

And good riddance to leap seconds! It was too hard for us to figure out, and they didn't do anything useful for anyone.

Right, we have the capability to update timezone definitions in a standardized automatable way right now, but 14 hours is the furthest timezone offset a political timezone has ever had. The distant future will require the offset to drift by multiple earth rotations, which puts a wrench in the flexibility of existing systems even if the tzdata database compiles properly. For example, this would break Java's ZonedDateTime as it only supports offsets up to 18 hours.

Just define new epoch at the turn of a century. Like a "UTD" or "UT2" that begins like 2200/01/01 00:00 that is actually UTC 2199/12/31 11:43:21 or something. Then hardcode the magic TAI number in the headers along the gravity constant and such. Solves the time_t problem too if done every centuries; 2^32 seconds = 136.102208 years. The biggest concern will be that kids at that time will start asking why there was never been UTB and UTA, which our oldest grandkids wouldn't actually know why.

There is a bit of a fine line between caring about the future and not screwing them over, versus just being so arrogant as to think we know now the right thing to do for them.

But given the amount of time it is going to take to accumulate so much as another leap minute's worth of leap time, let alone an hour, I'm pretty confident we're in the "arrogant" branch if we start declaring what they need.

P(nobody cares about UTC anymore anyhow | someone had to solve the problem of incorporating non-terrestrial time which is way harder than leap seconds) would seem to me to approach 100%. You can decide which branch you want to take, but P(things just keep on keeping on without much change from today for the next several thousand years) seems not large enough to start trying to make lots of plans for.

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