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The leap second’s time is up: world votes to stop pausing clocks

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Re: The leap second’s time is up: world votes to stop pausing clocks

#161

Post by layer8 »

charcircuit wrote: post #79
adamsb6 wrote: post #50

Currently software has to be built to accommodate leap seconds. They happen frequently enough that you'll find out within a few years whether your software breaks when time suddenly skips forward or backward. If we kick the can down the road such that eventually we'll need to add a leap minute, we're going to end up with software that was never written to expect time to change in such a way, hasn't had a real world t…

There has never been a negative leap second. >If we kick the can down the road such that eventually we'll need to add a leap minute The drift is not in a single direction. The total drift is not going to be significant for a very long time if ever.

The total drift is accelerating long term, because the tidal deceleration of Earth‘s rotation due to the moon is quadratic.

Re: The leap second’s time is up: world votes to stop pausing clocks

#162

Post by lifthrasiir »

techdragon wrote: post #80

Hot take… Storing anything as UTC was a mistake and we should be using TAI for all storage and computation, only transforming into more human friendly formats for display to end users. This never needed to be a problem except we decided to make it harder to use TAI than UTC and so everything got built up off the backs of legacy bios level hardware supported UTC style clock behaviour, when we should have been using TA…

I now realized that the parent meant everything should have been TAI from the beginning, which is indeed a valid take. We can't switch to TAI today only because we are already using UTC.

Original comment: Only those who never tried to actually use TAI yourself can claim that you can use TAI instead of UTC without a problem.

Re: The leap second’s time is up: world votes to stop pausing clocks

#163

Post by friend_and_foe »

ars wrote: post #13

So we make things worse for humans in order to make it easier for computers? Yah, one second doesn't matter, but it builds up. This: "Or we could even decouple our sense of time from the Sun entirely, to create a single world time zone in which different countries see the Sun overhead at different times of day or night." Shows that they are completely disconnect from human reality: "Science already doesn’t use local…

I agree with you quite a bit here, although I'm of the persuasion that this one minute a century drift is nothing, you already deal with orders of magnitude worse when you go visit family in another time zone for example, and you're fine.

I think this goes along the lines of the great DST debate, the US is going to do away with the changes next year and make DST permanent. Not do away with it, keep it, forever.

Fundamentally we create these abstractions and begin to rely on them and then decouple how we operate from the real world. We created the clocks to measure the position of the sun in the sky, now we ignore the sun entirely, the clocks are god now. I don't think it's a good thing generally speaking, but on this particular issue, I don't think people are going to really feel anything different happening, it will decrease the engineering burden to constantly maintain and update systems, which means decreased resource consumption, with no noticeable impact on the day to day lives of anyone except those engineers relying on exact time measurement.

Re: The leap second’s time is up: world votes to stop pausing clocks

#164

Post by zokier »

finnh wrote: post #97

> The CGPM — which also oversees the international system of units (SI) — has proposed that no leap second should be added for at least a century, allowing UT1 and UTC to slide out of sync by about 1 minute. So, in one century, we'll get 1 minute's worth of drift. Recall that we all share the same clock within timezones, and 1 minute of drift between atomic & solar clocks is the equivalent of traveling 1/60th of your…

And of course there are things like Spain being in utc+1 despite sitting almost entirely west of Greenwich.

Re: The leap second’s time is up: world votes to stop pausing clocks

#165

Post by School-Cotton »

AnotherGoodName wrote: post #160
School-Cotton wrote: post #125

Earlier quoted context omitted.

Why would we ever need a leap minute? Just let time zones drift. Unless you happen to be at the exact longitude for which your time zone is correct, the sun's not at its highest point in the sky for you at exactly noon anyway. Eventually, thousands of years from now when time has drifted by an hour or more (assuming modern technological civilization even still exists by then), each jurisdiction can just change their…

The last part is right and is also why we have this problem. Leap seconds are an architectural blunder that always belonged in the abstraction layer that lines up the sun with the rotation of earth (the time zone abstraction). It never belonged in the part that counts seconds.

That's a great way of putting it!

Re: The leap second’s time is up: world votes to stop pausing clocks

#166

Post by krick »

techdragon wrote: post #80

Hot take… Storing anything as UTC was a mistake and we should be using TAI for all storage and computation, only transforming into more human friendly formats for display to end users. This never needed to be a problem except we decided to make it harder to use TAI than UTC and so everything got built up off the backs of legacy bios level hardware supported UTC style clock behaviour, when we should have been using TA…

I'm not sure I support your "hot take" — it is hot and requires a lot of contemplation. But that's not the point, IMO.

The point is, that there ALREADY EXIST both TAI and UTC. TAI is true monotonic (whatever it means in a relativistic universe) and doesn't make any compromises. UTC abolishes monotonicity in order to keep both the length of a second and the time relationship to the orbital rotation. They both work. For whatever reason (for obvious reasons that is, but doesn't matter) UTC was chosen in virtually any software system to keep time.

So, ok, if there is a suspicion of leap seconds being unnecessary. How about moving from UTC time to TAI then? Let's keep UTC as it is, keep adding leap seconds and just make it a best practice to rely on TAI for all datetime operations and world clock synchronization? Maybe it will work out, maybe it won't, but at least you won't be breaking a perfectly working alternative (currently — mainstream) system.

The more I think about it, the more outrageously stupid abolishing leap seconds seems.

Re: The leap second’s time is up: world votes to stop pausing clocks

#167

Post by benlivengood »

techdragon wrote: post #80

Hot take… Storing anything as UTC was a mistake and we should be using TAI for all storage and computation, only transforming into more human friendly formats for display to end users. This never needed to be a problem except we decided to make it harder to use TAI than UTC and so everything got built up off the backs of legacy bios level hardware supported UTC style clock behaviour, when we should have been using TA…

As spacecraft start making return trips to Earth we'll run into similar adjustment problems because TAI doesn't progress at the same rate at different altitudes and accelerations, so there'll need to be a re-sync at some point. Satellites already have a similar problem but can just use direct synchronization with Earth since it's so close. In theory spacecraft could do the same direct synchronization to Earth time, but e.g. a computer on the dark side of the moon would need additional relay(s) to stay in sync.

I'm not sure why we don't define an intergalactic time standard and approximate that everywhere with NTP-like protocols; one monotonic clock at rest (with respect to CMBR) in free space. The second is weirdly defined/tracked in Earth's gravity well.

Re: The leap second’s time is up: world votes to stop pausing clocks

#168

Post by ars »

soggybutter wrote: post #63
ars wrote: post #13

So we make things worse for humans in order to make it easier for computers? Yah, one second doesn't matter, but it builds up. This: "Or we could even decouple our sense of time from the Sun entirely, to create a single world time zone in which different countries see the Sun overhead at different times of day or night." Shows that they are completely disconnect from human reality: "Science already doesn’t use local…

I struggle to understand how we benefit that much from the same wall clock times mapping roughly to the same times of day across time zones. It seems like there's pros and cons to both ways and there's no clear "better" option when it comes to the human experience. Meanwhile, doing away with timezones also does away with a lot of complexity both in computing and other areas (e.g. scheduling across timezones)

This will help you understand: https://qntm.org/abolish

Re: The leap second’s time is up: world votes to stop pausing clocks

#169

Post by justinpombrio »

hoytech wrote: post #103

In 2015 I was working at a "fintech" company and a leap second was announced. It was scheduled for a Wednesday, unlike all others before which had happened on the weekend, when markets were closed. When the previous leap second was applied, a bunch of our Linux servers had kernel panics for some reason, so needless to say everyone was really concerned about a leap second happening during trading hours. So I was assig…

> I'm not sure what the moral is here, if there is one.

Always procrastinate :-)

Re: The leap second’s time is up: world votes to stop pausing clocks

#170

Post by jsymolon »

ARandomerDude wrote: post #117
Akronymus wrote: post #35

Earlier quoted context omitted.

Wouldn't work afaict. You'd have to get rid of the mass, not just explode it.

“Sir, are you suggesting that we blow up the moon?”

Nope, just explosive rapid deconstruction.
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