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  • - I'm just outside the town of Gudhjem

  • on the northeast coast of Bornholm in Denmark.

  • It's a little out of the way.

  • To get to this point from Copenhagen

  • I had to drive across the Oresund bridge and through Sweden...

  • GPS: "Take the second exit and stay on 'Dag-hammer-schultz-vag'."

  • ...then take a 90 minute ferry ride, and then drive across the island.

  • But this island, or more specifically, a north-south line across this island

  • starting right here, is the only bit of Denmark that is exactly

  • 15 degrees east of Greenwich in London, exactly 1/24th of the way around the Earth.

  • which means that the sun is highest in the sky here

  • exactly one hour before Greenwich.

  • This lines defines Central European Time for Denmark.

  • To explain why there's a problem with that,

  • we need to talk to someone back where I started.

  • - The observatory we are seeing here

  • used to be the official timekeeping of Denmark,

  • so it actually provided what time the national time in Denmark was.

  • In 1893 a law was put in effect in Denmark,

  • at which point the time of Denmark was synchronised with international time zones.

  • So at that point in time, communications, transportation across borders

  • had become so fast, so international that it was becoming a problem

  • that every country had its own national timescale.

  • - Back before railways and modern telecommunications,

  • every town and village in the world ran on its own time.

  • 12 o'clock was when the sun was highest in the sky, on average, wherever you were.

  • That's called mean solar noon.

  • Once the world started to move fast enough, though,

  • every town and village having its own time became a problem.

  • And steadily over decades, governments agreed that the official legal time

  • would be the same in each region, in each time zone.

  • And that each time zone would be offset by a round number

  • compared to the time at Greenwich in London.

  • The closest round number to Copenhagen was one hour, 15 degrees east,

  • and so Denmark chose that.

  • The clocks everywhere in the country were changed to agree with mean solar noon

  • at this line.

  • But then along came the Information Age,

  • and it turned out that wasn't quite good enough

  • because the Earth wobbles.

  • - Earth wobbles a bit in its rotation

  • and that means that it's not exactly the same all year round,

  • and more than that, Earth rotation also slows a bit over time

  • because of tidal forces from the Moon.

  • If we were actually, in Denmark to follow our own time,

  • like our mean solar time,

  • we would be off with some hundredths of a second,

  • and this would actually make it difficult

  • for Danish financial companies, for instance,

  • to actually trade on stock markets.

  • - Once humanity had got the ability to track the Earth's rotation precisely

  • we found out that noon drifts a little,

  • by a tiny and different fraction of a second each day.

  • And when computers, and clocks, and scientists around the world

  • need to be accurate to within that tiny fraction of a second,

  • that's a problem.

  • So the scientific community agreed to ignore the wobble

  • and created Coordinated Universal Time, UTC,

  • which doesn't care about the Earth's movement.

  • To your phone, your computer and to your bank,

  • to basically everyone apart from astronomers,

  • a day is precisely 86,400 seconds.

  • As measured by the average of a network of atomic clocks around the world.

  • If you want to be really detailed, then on screen is the full formal definition of a day.

  • And every time the Earth's wobble threatens to drift out of sync

  • with our standard, we add a leap second to UTC,

  • either skipping a second or counting a second twice

  • to get UTC back in line with the annoyingly real Earth and stars.

  • The catch is, [sighs] Denmark never updated its laws.

  • - The official law in Denmark is defined by a law from 1893

  • which states that Denmark follows mean solar time.

  • In reality Denmark follows the Universal Coordinated Time,

  • the atomic clock time which is used all around the world.

  • So I made a petition to Parliament in Denmark

  • to try to change this law.

  • Some Danish media took up this story

  • and following that, a member of the Danish Parliament

  • actually made a question to the minister,

  • and the minister then said that he

  • was actually interested in looking into this

  • and maybe make changes to the law.

  • - As I record this, the error is tiny,

  • it's only about .04 seconds,

  • but that's just based on when I happen to be filming here.

  • By the time this video goes live,

  • the error is predicted to be at about .06 seconds.

  • By the end of the year, it'll be about a quarter of a second.

  • I've written some code that will keep checking the clocks and automatically

  • update the title of this video as we go.

  • At least until the code breaks and I can't be bothered to fix it anymore.

  • The error could get all the way to .9 seconds

  • before a leap second arrives to correct it.

  • But it's not like phones, and computers and stock exchanges here in Denmark

  • follow Danish law. They don't pay attention to the stars.

  • They all just use UTC instead, and ignore the outdated legislation.

  • So does it matter?

  • - I think that laws should in general

  • be in accordance with reality [laughs]

  • and if not you should at least

  • decide that we want to keep it this way actively.

  • Denmark does not have any official time laboratory,

  • so we rely on the time services from neighbouring countries.

  • This may put us at a disadvantage compared to other countries.

  • - If everyone agrees to ignore a law,

  • and the government doesn't care to enforce it, that's fine.

  • As long as the government keeps deciding not to enforce that law

  • and also to ignore the hypocrisy

  • that government is ignoring its own laws.

  • Fixing that shouldn't be the highest thing on the priority list,

  • but it'd be nice to do it at some point.

  • After all the United States moved to UTC in 2007 with the America COMPETES Act.

  • And the UK...

  • Ah. Er. [clears throat]

  • Y'know, it's probably not a good time

  • to bother the British government right now.

  • It can wait.

  • We've got time.

- I'm just outside the town of Gudhjem

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デンマークが世界と0.23秒差の理由 (Why Denmark Is .23 Seconds Behind The World)

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    林宜悉 に公開 2021 年 01 月 14 日
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