this post was submitted on 14 Dec 2023
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It's not just time zones and leap seconds. SI seconds on Earth are slower because of relativity, so there are time standards for space stuff (TCB, TGC) that use faster SI seconds than UTC/Unix time. T2 - T1 = [God doesn't know and the Devil isn't telling.]

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[–] [email protected] 25 points 10 months ago* (last edited 10 months ago) (5 children)

Not even going to general relativity, as this comics suggests to experience time slowing down due to gravity, the events are not just at time, but also at particular location in space relative particular inertial system. Not specifying it, and not specifying the inertial system for which the final answer is needed makes it impossible to calculate even in special relativity, without effects of gravity.

[–] [email protected] 27 points 10 months ago* (last edited 10 months ago) (1 children)

Here's the shortlist of horrors I've had to deal with in my career:

  • Mixed US/ROW short date formats - DD/MM/YY, MM/DD/YY
  • mixed timezones in the same column
  • the wrong timezone (marked as PDT but actually UTC, or sometimes the other way around)
  • clock drift
  • timezones again...because timezones suck
  • historical timezones
  • NTP configurations

Things I've read about but haven't needed to deal with personally:

  • leap seconds
  • clock slew vs skip
  • hardware clocks
  • PTP

The one thing I really don't care about is relativity

[–] [email protected] 4 points 10 months ago

it's all relative anyway

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