3 ms·

No. UTC with leap seconds isn't "reality" except in the sense that some of those awful scripted "reality TV" shows are reality. It's a confection, and it's anno

No. UTC with leap seconds isn't "reality" except in the sense that some of those awful scripted "reality TV" shows are reality. It's a confection, and it's annoying so there's no real argument for it beyond "That's what we've always done" which is a pretty dubious rationale for anything, but even more so when it's been like that for less than a normal human lifespan. Leap seconds won't even be like the automobile, let alone newspapers or hotdogs, they're a fleeting idea we thought might be good, now we realise it's not good, so bye bye. There are two "realities" here. TAI is the monotonically increasing "Seconds are the same length and happen in order" clock time that it turns out well suits a lot of human enterprises. The exact details have been worked out pretty well. A Day in TAI is 24 hours of 60 minutes of 60 SI seconds, always, forever. UT1 is a descendant of "Solar time" now based on the Earth's rotational angle. A Day in UT1 is the full rotation, how long that is in SI seconds varies very slightly and arbitrarily. UTC wants to have the steady monotonicity of TAI except it wants to match UT1's days exactly, this is not a thing, so the "leap seconds" are conjured to kludge it. This kludge is what's going away, it's not part of "reality" it's a kludge to try to fit a square peg in a round hole and we're giving up the kludge. It has been a long time since humans worked purely from direct observation of the "solar time" or rotation. Once the clock gets invented, so millennia ago, that's out and humans are measuring (albeit not very precisely at first) what we now call TAI. Giving up leap seconds is us finally accepting that while UT1 is astronomically interesting, it's not actually a sensible basis for day to day living.

GJim 3y ago
> while UT1 is astronomically interesting, it's not actually a sensible basis for day to day living. Hard disagree! Allowing ones clocks to gradually drift from the behaviour of the Earth (which regulates our biological lives) is a mess. Once can compare the eventual correction that will be required akin to the shift from the Julian to Gregorian calendar and the problems that caused. TAI was always there for those who needed it.
- zarzavat 3y ago
  A leap minute every few centuries makes much more sense than a leap second every few years. We have until our great-great-grandchildren to prepare.
  - GJim 3y ago
    That really is the motherload of technical debt. This discussion really is highlining the cultural differences between software engineers and other engineering fields.
    - zarzavat 3y ago
      Not really. Adding leap seconds at the end of years is inferior because a year is a human-scale duration. Planning something “next year” is human-scale. Planning something “next century” is not human-scale because I won’t be alive then. If we use leap minutes then most people will not see one in their lifetime, compared to everyone seeing multiple leap seconds in their lifetime.
      - ChrisSD 3y ago
        But when that leap minute does eventually occur, it's going to cause havoc in all the systems that don't handle it. Which, let's face it, there are going to be a lot of. Either because they were never designed for it or else the relevant code paths were never actually tested.
        mminer237 3y ago
        You could broadcast a leap minute with a decade to prepare for it and most software would still be developed, used, and die off in the 90 years in between. It's better for 15% of relevant software to have to worry about something so consequentially minor than 100%.
        scheme271 3y ago
        That didn't work so well for y2k issues. Just this month there was an article about a woman that keeps getting id'ed as being 1 year old instead of 101 years old because of a y2k fix.
- zamadatix 3y ago
  The drift (a second every ~1.5 years) is so small the accumulation is irrelevant to biological processes. 2000 years from now it does not matter that solar time has drifted ~an hour. Beyond "what people millennia ago used to do at 7 we do at when the clock says 8" not being a problem (assuming we even live similar lives) I'll be god damned if we can stop ourselves from changing zones and whether or not we'll observe DST this year for the next 20 years let alone what else we'll muck up in the next 2000. TAI will still be there and needed by folks. UTC is stopping adding leap seconds in the future, not reverting back as if it never had any.
  - throw0101d 3y ago
    > The drift (a second every ~1.5 years) is so small the accumulation is irrelevant to biological processes. It is irrelevant until it is not: just ask Julius Caesar and Pope Gregory XIII. > Beyond "what people millennia ago used to do at 7 we do at when the clock says 8" not being a problem […] The difference of an hour does make a difference, as sleep researchers and chronobiologists keep pointing out every time a discussion on DST comes up (it is not just about the sudden time jump, but also about the actual time): * https://www.frontiersin.org/articles/10.3389/fphys.2019.00944/full https://www.frontiersin.org/articles/10.3389/fphys.2019.0094... * https://sleepresearchsociety.org/wp-content/uploads/2022/11/zsac236.pdf https://sleepresearchsociety.org/wp-content/uploads/2022/11/... * https://srbr.org/wp-content/uploads/2018/10/SRBR-Statement-on-DST.pdf https://srbr.org/wp-content/uploads/2018/10/SRBR-Statement-o... * http://www.chronobiocanada.com/official-statements http://www.chronobiocanada.com/official-statements
    - 01HNNWZ0MV43FF 3y ago
      If a difference of an hour that's been there your entire life is noticeable, we should be able to observe that as a discontinuity of quality of life at time zone boundaries.
    - zamadatix 3y ago
      > It is irrelevant until it is not: just ask Julius Caesar and Pope Gregory XIII. You're refferring to needing to reform the entire calendar but this doesn't make sense in context of me explaining that the calendar itself never needs to be reformed in the first place. That the sun was a few degrees different in the sky for Julius Caesar when a modern clock reads 3 PM in his time is not inherently a problem as Julius Caesar wouldn't have the same norms as you do in terms of what wall time is acceptable for waking/sleeping/eating/working/etc. E.g. 20,000 years from now if a clock reads 3 AM during midday it' not a problem as society will have had 20,000 years to adjust 12 hours vs your referenced calendar reforms that changed everything overnight. > The difference of an hour does make a difference, as sleep researchers and chronobiologists keep pointing out every time a discussion on DST comes up (it is not just about the sudden time jump, but also about the actual time): Again, you're missing the forest through the trees - though in two different ways here. The first is that it's a minute over someone's (long) life, so what impact we feel when we change time by an hour twice a year isn't relevant. The second is that society, over 2,000 years, does not need to change timekeeping itself to wake up when the clock says 8 instead of 7. If the change were to happen over a short period then sure, it's not really feasible for society to move up what wall time their breakfast is four times a year or something, but an hour a millenia isn't even something society needs to consciously worry about. My point is not that we don't have a biological clock, it's that the effect of leap seconds on a human's biological clock are too small to affect it. One of your sources already says it's 15-20 minutes misaligned a day, why are you using it to argue 1 additional minute for your entire life is impactful? On the long term societal scale my point is society won't always agree we should wake up when the wall clock says 7 am. That norm changing shifting ~an hour 2,000 years is not a relevant concern for changing the way we keep time.
amiga386 3y ago
> UTC with leap seconds isn't "reality" Weeks aren't reality. Timezones aren't reality. Julian/Gregorian calendar months aren't reality. But they are essential. Calendars, centralised time, and timezones drive coordinated human socialisation and commerce, increasing the wealth of all nations. Countries have switched timezones so that their "work day" matches another more prosperous country's "work day" Humans want, and have always wanted, a compromise between their activities, and the unalterable reality of nature. We have "daylight savings time" because if we say "work is between 9AM and 5PM", that allows for the synchronised commerce - you can phone another business at 9AM because you both start work at 9AM, and 9AM = 9AM for both of you. But the reality is that in the winter months, everyone is going to work or leaving work in darkness, with no daylight time for socialisation. So you shift your entire country's (or state's) offset from an absolute clock, to turn "9AM to 5PM" into "8AM to 4PM" without actually stating that, because if businesses started varying their hours, they'd desync completely and you'd never get business done again. It hasn't been that long since we accepted centralised time, only really since the invention of railways, and especially since the invention of the telegraph. Prior to that, local solar time ruled. Bram Stoker was particulary upset that Ireland was 25 minutes out of alignment with Great Britain (Dublin Mean Time vs Greenwich Mean Time), in his view Ireland was missing out on a lot of trade [0] I don't think we're going to move to a time source that will slowly desync us from nature. If we liked being desynced from nature, we've have ditched DST by now - we haven't. And we also haven't gone entirely back to nature and made it 9:30 in Dublin when it's 9:55 in London. I think we're going to remain on this middle path - fudging the mixture of atomic time and alignment with solar time - for the rest of our days on this planet. [0] https://www.thefitzwilliam.com/p/turning-back-the-economic-clock https://www.thefitzwilliam.com/p/turning-back-the-economic-c...
- lmm 3y ago
  > Weeks aren't reality. Timezones aren't reality. Julian/Gregorian calendar months aren't reality. But they are essential. And we ignore all of those in computer "system" clocks, and track them in a secondary local time layer, quite rightly. We should have handled leap seconds the same way.

GJim 3y ago

> while UT1 is astronomically interesting, it's not actually a sensible basis for day to day living. Hard disagree! Allowing ones clocks to gradually drift from the behaviour of the Earth (which regulates our biological lives) is a mess. Once can compare the eventual correction that will be required akin to the shift from the Julian to Gregorian calendar and the problems that caused. TAI was always there for those who needed it.

zarzavat 3y ago
A leap minute every few centuries makes much more sense than a leap second every few years. We have until our great-great-grandchildren to prepare.
- GJim 3y ago
  That really is the motherload of technical debt. This discussion really is highlining the cultural differences between software engineers and other engineering fields.
  - zarzavat 3y ago
    Not really. Adding leap seconds at the end of years is inferior because a year is a human-scale duration. Planning something “next year” is human-scale. Planning something “next century” is not human-scale because I won’t be alive then. If we use leap minutes then most people will not see one in their lifetime, compared to everyone seeing multiple leap seconds in their lifetime.
    - ChrisSD 3y ago
      But when that leap minute does eventually occur, it's going to cause havoc in all the systems that don't handle it. Which, let's face it, there are going to be a lot of. Either because they were never designed for it or else the relevant code paths were never actually tested.
      - mminer237 3y ago
        You could broadcast a leap minute with a decade to prepare for it and most software would still be developed, used, and die off in the 90 years in between. It's better for 15% of relevant software to have to worry about something so consequentially minor than 100%.
        scheme271 3y ago
        That didn't work so well for y2k issues. Just this month there was an article about a woman that keeps getting id'ed as being 1 year old instead of 101 years old because of a y2k fix.
zamadatix 3y ago
The drift (a second every ~1.5 years) is so small the accumulation is irrelevant to biological processes. 2000 years from now it does not matter that solar time has drifted ~an hour. Beyond "what people millennia ago used to do at 7 we do at when the clock says 8" not being a problem (assuming we even live similar lives) I'll be god damned if we can stop ourselves from changing zones and whether or not we'll observe DST this year for the next 20 years let alone what else we'll muck up in the next 2000. TAI will still be there and needed by folks. UTC is stopping adding leap seconds in the future, not reverting back as if it never had any.
- throw0101d 3y ago
  > The drift (a second every ~1.5 years) is so small the accumulation is irrelevant to biological processes. It is irrelevant until it is not: just ask Julius Caesar and Pope Gregory XIII. > Beyond "what people millennia ago used to do at 7 we do at when the clock says 8" not being a problem […] The difference of an hour does make a difference, as sleep researchers and chronobiologists keep pointing out every time a discussion on DST comes up (it is not just about the sudden time jump, but also about the actual time): * https://www.frontiersin.org/articles/10.3389/fphys.2019.00944/full https://www.frontiersin.org/articles/10.3389/fphys.2019.0094... * https://sleepresearchsociety.org/wp-content/uploads/2022/11/zsac236.pdf https://sleepresearchsociety.org/wp-content/uploads/2022/11/... * https://srbr.org/wp-content/uploads/2018/10/SRBR-Statement-on-DST.pdf https://srbr.org/wp-content/uploads/2018/10/SRBR-Statement-o... * http://www.chronobiocanada.com/official-statements http://www.chronobiocanada.com/official-statements
  - 01HNNWZ0MV43FF 3y ago
    If a difference of an hour that's been there your entire life is noticeable, we should be able to observe that as a discontinuity of quality of life at time zone boundaries.
  - zamadatix 3y ago
    > It is irrelevant until it is not: just ask Julius Caesar and Pope Gregory XIII. You're refferring to needing to reform the entire calendar but this doesn't make sense in context of me explaining that the calendar itself never needs to be reformed in the first place. That the sun was a few degrees different in the sky for Julius Caesar when a modern clock reads 3 PM in his time is not inherently a problem as Julius Caesar wouldn't have the same norms as you do in terms of what wall time is acceptable for waking/sleeping/eating/working/etc. E.g. 20,000 years from now if a clock reads 3 AM during midday it' not a problem as society will have had 20,000 years to adjust 12 hours vs your referenced calendar reforms that changed everything overnight. > The difference of an hour does make a difference, as sleep researchers and chronobiologists keep pointing out every time a discussion on DST comes up (it is not just about the sudden time jump, but also about the actual time): Again, you're missing the forest through the trees - though in two different ways here. The first is that it's a minute over someone's (long) life, so what impact we feel when we change time by an hour twice a year isn't relevant. The second is that society, over 2,000 years, does not need to change timekeeping itself to wake up when the clock says 8 instead of 7. If the change were to happen over a short period then sure, it's not really feasible for society to move up what wall time their breakfast is four times a year or something, but an hour a millenia isn't even something society needs to consciously worry about. My point is not that we don't have a biological clock, it's that the effect of leap seconds on a human's biological clock are too small to affect it. One of your sources already says it's 15-20 minutes misaligned a day, why are you using it to argue 1 additional minute for your entire life is impactful? On the long term societal scale my point is society won't always agree we should wake up when the wall clock says 7 am. That norm changing shifting ~an hour 2,000 years is not a relevant concern for changing the way we keep time.

amiga386 3y ago

> UTC with leap seconds isn't "reality" Weeks aren't reality. Timezones aren't reality. Julian/Gregorian calendar months aren't reality. But they are essential. Calendars, centralised time, and timezones drive coordinated human socialisation and commerce, increasing the wealth of all nations. Countries have switched timezones so that their "work day" matches another more prosperous country's "work day" Humans want, and have always wanted, a compromise between their activities, and the unalterable reality of nature. We have "daylight savings time" because if we say "work is between 9AM and 5PM", that allows for the synchronised commerce - you can phone another business at 9AM because you both start work at 9AM, and 9AM = 9AM for both of you. But the reality is that in the winter months, everyone is going to work or leaving work in darkness, with no daylight time for socialisation. So you shift your entire country's (or state's) offset from an absolute clock, to turn "9AM to 5PM" into "8AM to 4PM" without actually stating that, because if businesses started varying their hours, they'd desync completely and you'd never get business done again. It hasn't been that long since we accepted centralised time, only really since the invention of railways, and especially since the invention of the telegraph. Prior to that, local solar time ruled. Bram Stoker was particulary upset that Ireland was 25 minutes out of alignment with Great Britain (Dublin Mean Time vs Greenwich Mean Time), in his view Ireland was missing out on a lot of trade [0] I don't think we're going to move to a time source that will slowly desync us from nature. If we liked being desynced from nature, we've have ditched DST by now - we haven't. And we also haven't gone entirely back to nature and made it 9:30 in Dublin when it's 9:55 in London. I think we're going to remain on this middle path - fudging the mixture of atomic time and alignment with solar time - for the rest of our days on this planet. [0] https://www.thefitzwilliam.com/p/turning-back-the-economic-clock https://www.thefitzwilliam.com/p/turning-back-the-economic-c...

lmm 3y ago
> Weeks aren't reality. Timezones aren't reality. Julian/Gregorian calendar months aren't reality. But they are essential. And we ignore all of those in computer "system" clocks, and track them in a secondary local time layer, quite rightly. We should have handled leap seconds the same way.