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No leap second will be introduced at the end of December 2026

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Re: No leap second will be introduced at the end of December 2026

#251

Post by tialaramex »

dmurray wrote: post #242
tialaramex wrote: post #232

Earlier quoted context omitted.

The thing is, an SF MP can't vote or debate because they, by policy, refuse to attend. You're correct that the party has representatives in the other bodies which it does recognise but those aren't the same people. So for example Órfhlaith Begley was elected MP for West Tyrone. Her voters will have known she's not going to Westminster, and she didn't - but she's not in some parallel institution instead, AFAIK there i…

But Órfhlaith Begley does go to Westminster, and she has an access badge for the Houses of Parliament, and she flies over there and works in her office in the parliament buildings and answers her @parliament.co.uk emails and asks her staffers (paid for by the parliament) to respond to letters on paper headed Órfhlaith Begley MP. All the work of an MP except the most performative part. She just doesn't go into the roo…

Fascinating, I didn't know that they actually physically travel to Westminster. That does seem like quite a trip given they could work from home. I'm also not sure how effective you can be in this way, but of course it's really up to her constituents not me whether they feel adequately represented.

I think it's parliament.uk rather than parliament.co.uk by the way.

Re: No leap second will be introduced at the end of December 2026

#252

Post by donall »

tialaramex wrote: post #232
donall wrote: post #193

Earlier quoted context omitted.

Agree that SF is not a protest vote but they do vote and debate. Since their first major electoral victory over 100 years ago they have been clear that they represent their constituents to the best of their abilities (I won't opine on the quality of representation in this forum). That has always involved a cabinet, votes, debates, and eventually a bicameral legislature. The key aspect is that they consider the Englis…

The thing is, an SF MP can't vote or debate because they, by policy, refuse to attend. You're correct that the party has representatives in the other bodies which it does recognise but those aren't the same people. So for example Órfhlaith Begley was elected MP for West Tyrone. Her voters will have known she's not going to Westminster, and she didn't - but she's not in some parallel institution instead, AFAIK there i…

You're absolutely right that they aren't in a parallel institution. As I understand it, the SF perspective is that there is no legitimate government representing the people of West Tyrone (other than Stormont, which is complicated). I think it sounds like we're saying the same thing but there's a subtle interpretation difference. When Idi Amin declared himself to be the King of Scotland the Scots didn't send representatives to Uganda to form a government. The SF position since their Árd Fheis before the 1919 elect has been to treat Westminster like Idi Amin. To simply engage in a conversation about Idi Amin's claim to the throne of Scotland would be to give him too much credibility.

So the core issue, from the Republican perspective, is that the people of West Tyrone are denied representation at the national level in Ireland by a foreign government. Once that representation is achieved the SF representatives will participate in it. (again, not trying to address the merits; just clarify the logic)

Re: No leap second will be introduced at the end of December 2026

#253

Post by Dylan16807 »

pdonis wrote: post #248
Dylan16807 wrote: post #201

Earlier quoted context omitted.

> Um, because it's the prime meridian and that's how UTC is defined? That's an explanation of how it is, not why we should care to preserve it. The definitions of hours minutes and seconds have changed before, and in recent history. > Which is why I was careful to specify mean solar noon. And "mean solar noon" is meaningless to people's lives. Even in the areas where time zones do follow meridians and not country bor…

> The definitions of hours minutes and seconds have changed before, and in recent history. In terms of what physical process we use to set the standard, yes. But those very changes were made to try to preserve the same time periods that were important to humans. In other words, to not change what hours, minutes, and seconds mean intuitively to us humans as we go about our daily lives.

I completely disagree. The intuitive meaning is that a day is 24 hours and you can divide that by 60 twice. But that makes the second vary by some parts per billion, so we nailed down the second to make the technical side easier at the expense of relatability.

Re: No leap second will be introduced at the end of December 2026

#254

Post by pdonis »

Dylan16807 wrote: post #253
pdonis wrote: post #248

Earlier quoted context omitted.

> The definitions of hours minutes and seconds have changed before, and in recent history. In terms of what physical process we use to set the standard, yes. But those very changes were made to try to preserve the same time periods that were important to humans. In other words, to not change what hours, minutes, and seconds mean intuitively to us humans as we go about our daily lives.

I completely disagree. The intuitive meaning is that a day is 24 hours and you can divide that by 60 twice. But that makes the second vary by some parts per billion, so we nailed down the second to make the technical side easier at the expense of relatability.

> we nailed down the second to make the technical side easier at the expense of relatability.

Would you also say that getting rid of leap seconds and allowing UTC to gradually drift away from the sun is making the technical side easier at the expense of relatability?

Re: No leap second will be introduced at the end of December 2026

#255

Post by pdonis »

Dylan16807 wrote: post #253
pdonis wrote: post #248

Earlier quoted context omitted.

> The definitions of hours minutes and seconds have changed before, and in recent history. In terms of what physical process we use to set the standard, yes. But those very changes were made to try to preserve the same time periods that were important to humans. In other words, to not change what hours, minutes, and seconds mean intuitively to us humans as we go about our daily lives.

I completely disagree. The intuitive meaning is that a day is 24 hours and you can divide that by 60 twice. But that makes the second vary by some parts per billion, so we nailed down the second to make the technical side easier at the expense of relatability.

> The intuitive meaning is that a day is 24 hours and you can divide that by 60 twice.

And that's exactly why the SI second has the length that it has--to be as close as possible in terms of how atomic clocks work to 1/86400 of an Earth mean solar day at a chosen epoch. (Note that the actual definition before the atomic clock one was adopted was in terms of the Earth's tropical year at that epoch--but the fraction of the tropical year that was chosen was to line up the second with 1/86400 of an epoch day.) If we didn't care about "relatability", nobody would have gone to all the trouble of trying to determine how many cesium clock oscillations there were in 1/86400 of an epoch day.

Re: No leap second will be introduced at the end of December 2026

#256

Post by pdonis »

Dylan16807 wrote: post #253
pdonis wrote: post #248

Earlier quoted context omitted.

> The definitions of hours minutes and seconds have changed before, and in recent history. In terms of what physical process we use to set the standard, yes. But those very changes were made to try to preserve the same time periods that were important to humans. In other words, to not change what hours, minutes, and seconds mean intuitively to us humans as we go about our daily lives.

I completely disagree. The intuitive meaning is that a day is 24 hours and you can divide that by 60 twice. But that makes the second vary by some parts per billion, so we nailed down the second to make the technical side easier at the expense of relatability.

> The intuitive meaning is that a day is 24 hours

Ok so far.

> and you can divide that by 60 twice

I'm not so sure. The concept of 24 hours in a day originates in civil timekeeping, yes, but not minutes and seconds. Those originally came from astronomy, and corresponded to angles, not times, and those angles are constants; they don't change as the Earth's rotation slows down or as its speed in orbit around the Sun changes over the course of a year. I don't think people's intuitive concept of minutes and seconds is that they vary according to the time of year or the tidal effects on the Earth.

Re: No leap second will be introduced at the end of December 2026

#257

Post by Dylan16807 »

pdonis wrote: post #256
Dylan16807 wrote: post #253

Earlier quoted context omitted.

I completely disagree. The intuitive meaning is that a day is 24 hours and you can divide that by 60 twice. But that makes the second vary by some parts per billion, so we nailed down the second to make the technical side easier at the expense of relatability.

> The intuitive meaning is that a day is 24 hours Ok so far. > and you can divide that by 60 twice I'm not so sure. The concept of 24 hours in a day originates in civil timekeeping, yes, but not minutes and seconds. Those originally came from astronomy, and corresponded to angles, not times, and those angles are constants; they don't change as the Earth's rotation slows down or as its speed in orbit around the Sun ch…

I'm going to do one reply to all of yours:

> I don't think people's intuitive concept of minutes and seconds is that they vary according to the time of year or the tidal effects on the Earth.

But if you asked people to choose between "seconds vary by an imperceptible amount, less than your clocks naturally drift" and "an hour doesn't have 3600 seconds" I bet most will pick the former.

And it doesn't have to drift day by day, you can average it over a multi-year period.

It's going to be weird once the earth slows down enough that we'd need a leap second every day or two. Once you can't ignore the drift anymore, the system we chose is significantly unintuitive.

> If we didn't care about "relatability", nobody would have gone to all the trouble of trying to determine how many cesium clock oscillations there were in 1/86400 of an epoch day.

I'm not saying we didn't care about it, I'm saying we didn't put it as top priority. We went with a nice clean fixed-length second that will drift away from the Earth over time. And it wasn't/isn't that hard to determine the number of oscillations since "matching" the Earth's unstable speed has a huge margin you can land within.

> Would you also say that getting rid of leap seconds and allowing UTC to gradually drift away from the sun is making the technical side easier at the expense of relatability?

Yes.

I'm in favor of both, to be honest. But it's a tradeoff, and it's a tradeoff that weakens the layman's definition of a second.

Re: No leap second will be introduced at the end of December 2026

#258

Post by bloppe »

_alternator_ wrote: post #50
doctoboggan wrote: post #30

What causes the unpredictability in this? I would have guessed we have earth's rotation and orbit down to many decimals. Does geological activity, weather, or something else cause rotation speed differences that we just can't predict?

In short, yes, the weather, geology, and signicantly, human movement of water via aquifer draining and dam building, as well as glaicial and ice melts, all contribute to unpredictable changes in the earths rotational period, as well as the axis of rotation. The models for this are IIRC trigonometric polynomials of fairly low order, so even if we could model the unpredictability perfectly, truncation error would limit…

Phasing out leap seconds is such a crack pot idea. Read the resolution [1]. The conclusion hinges entirely on accepting the immutability of these 2 premises:

  recalling that the CGPM at its 26th meeting (2018)
    - stated that UTC is the only recommended time scale for international reference and the basis of civil time in most countries,
    - recommended all relevant unions and organizations to work together to develop a common understanding on the realization and dissemination of reference time scales with a view to considering the present limitation on the maximum magnitude of UT1 - UTC to meet the needs of the current and future user communities,
I accept all the other premises from the resolution, but then the obvious conclusion should be to just recommend TAI instead of UTC for any application that could be disrupted by leap seconds, instead of butchering UTC and turning it into just a worse version of TAI.

[1]: https://www.bipm.org/en/cgpm-2022/resolution-4

Re: No leap second will be introduced at the end of December 2026

#259

Post by oconnore »

hdgvhicv wrote: post #219
alright2565 wrote: post #173

Earlier quoted context omitted.

> made CLOCK_MONOTONIC unclear in this regard I don't understand what you mean. Doesn't smearing still mean the clock only goes forward? It's still steadily incrementing. The only difference is that a second is slightly longer/shorter than you expect, but you already have to account for that if you're doing the kind of physics experiment where it would matter.

If you have one event per millisecond then you get 86,401,000 events on a day you smear, and that’s inconsistent with the 86,400,000 you get on days either side.

Sure but a system that breaks if it doesn't get exactly 86,400,000 millisecond scale scheduled events in a day has already been driving your SRE team insane.
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