Science Changes to the world's time scale debated.

[Notebook]

http://www.bbc.co.uk/news/science-environment-15546124

Save the Leap Second!
Write to your MP now, otherwise we all die earlier, or later.

N.

 

[Artlav]

Isn't it better to add an hour in a few centuries than constantly wreck havok with adding seconds every few years?

With timekeeping currently complicated as it is, a straightforward standard like MJD with no alterations for any events would be better.
Until you run into relativistic effects between planets in a few hundred years, that is.

Why should precision stuff run on civilian time?
GPS satellites can run on the straight time, nobody checks their clocks by them.
And conversion should be trivial if you know the offset, only keep it on the other side of straight time.

 

[Notebook]

"The International Earth Rotation Service monitors the Earth's activity, and they decide when it is appropriate to add a leap second into our time-scale," said Mr McEvoy

An informal survey by the ITU earlier this year revealed that three countries - the UK, China and Canada, are strongly against changing the current system.

However 13 countries, including the Unites States, France, Italy and Germany, want a new time-scale that does not have leap seconds. But with nearly 200 member states, this still leaves many others that have yet to reveal their position.

Could be fun next year when that lot start voting, must be some vested interests to cause a rumpus for something so abstract to most people?

I wonder if the International Earth Rotation Service does anything else, or are they just ready to tell everybody when the Earth stops rotating...?

N.

 

[Linguofreak]

What I'd go for would be to choose an epoch (such as the Unix epoch, though it doesn't have to be that), and, in scientific usage and other usage requiring precise times, simply use a count of seconds from that epoch as your universal time, with conversions of second counts to dates being simply a matter of human convenience for non-precision usage. Precision timekeeping should not need to be tied to any measure of time that can't be strictly defined as a number of seconds (for traditional measurements of time, this goes up to the hour, but nothing longer, as the value of the day, month, and year can shift (and the month has about fifty separate definitions to begin with), and I'm not aware of any traditional measurement of time on the scale of the day or longer that's not based on one of those three). And while time can be precisely measured in minutes and hours, it would be nice to do away with even these for scientific usage, in favor of power of ten multiples of the second (kilosecond, megasecond, etc, for consistency with metric), and/or power of two multiples of the second (for convenience with computers).

For everyday usage, we'd go on with pretty much the current system, with the understanding that it's precision is limited to within a second or two per year.

An example system would be to take the Unix epoch and add in the leap seconds accrued since the leap second was introduced in 1972 (Unix time as it currently exists keeps a count of the seconds from 0:00 UTC 1/1/1970, but does not count leap seconds, so it's 24 seconds off from the actual number of seconds since 0:00 UTC 1/1/1970). You would then have PUTC (Precision UTC), given as a second count from 0:00 UTC 1/1/1970, and NPUTC (Non-Precision UTC), given as a traditional date according to conversion tables. So 1320489148 PUTC (1320489124 by Unix time without leap seconds) would correspond to 10:32 NPUTC, Saturday, November 5th 2011.

 

[Artlav]

I wonder, are we so smart here to figure this out so easily, or does the panel of scientists voting on the issue know something we don't?

 

[statickid]

I was a huge fan of swatch's .beat watches, although prefer time zones and they are not very useful when noone else goes by beat time. a cool alternative that I found are scientific stopwatches that can measure time in decimal 1/100seconds, 1/1000decimal minutes, or 1/10000decimal hours. but it still has 24 hours and I would prefer the swatch decimal day, but they probably patented it or something. IF it was a usage rights issue, I think the SMARTER thing to do would be to make .beat decimal day free to be used by anyone so that people the society may be prone to switching over to it, thus making the companies watches actually flourish because people use the system of measurement, rather than 1 or 2 rich eccentric people owning it because it is "interesting." I converted a regular 12 hour clock to decimal time by removing the minute and second hands and changing the 12 hour faceplate to one with only 5 markings devided by 10s. it works awesome!

 

[Cras]

GPS satellites can run on the straight time, nobody checks their clocks by them.

Airliners tend to get their clocks set by the GPS.

 

[Jarvitä]

We should just throw out the astrological time system we currently use and measure time as epoch +- a number of seconds/nanoseconds/gigaseconds etc in the relativistic reference frame of the surface of Earth.

For epoch, either use the UNIX epoch (1970.1.1-00:00 UTC), or something equally sensible. Preferably, no mythology this time around.

EDIT: And for Cthulhu's sake, don't encode time as a regular int. Something like IEEE 754 (128 bit binary floating-point) should be good enough to work with acceptable precision from the beginning of the universe to the very, very distant future.

 

[N_Molson]

I converted a regular 12 hour clock to decimal time by removing the minute and second hands and changing the 12 hour faceplate to one with only 5 markings devided by 10s. it works awesome!

I would never had thought to do it that way. Brillant ! :idea:

 

[Jarvitä]

I was a huge fan of swatch's .beat watches, although prefer time zones and they are not very useful when noone else goes by beat time. a cool alternative that I found are scientific stopwatches that can measure time in decimal 1/100seconds, 1/1000decimal minutes, or 1/10000decimal hours. but it still has 24 hours and I would prefer the swatch decimal day, but they probably patented it or something. IF it was a usage rights issue, I think the SMARTER thing to do would be to make .beat decimal day free to be used by anyone so that people the society may be prone to switching over to it, thus making the companies watches actually flourish because people use the system of measurement, rather than 1 or 2 rich eccentric people owning it because it is "interesting." I converted a regular 12 hour clock to decimal time by removing the minute and second hands and changing the 12 hour faceplate to one with only 5 markings devided by 10s. it works awesome!

The purpose of decimal time is to eliminate the connection between measuring time and the astronomical cycles observed on Earth. Thus, the basic unit should be the second (or another unit that follows from a basic physical fact about the universe), not the day.

 

[T.Neo]

The problem is that the "epoch plus seconds" timekeeping system is absolutely and utterly meaningless in the real world, no matter how "science-y" it sounds.

Seriously. I started typing this post at 1 320 506 964. What?

Huh?

That 'time' makes absolutely no sense to me. It is just a random number. It might as well be 74 088. Or 761 390. Or 555 614 042.

It is without reference to anything. Humans are wired to think in terms of days and months and years.

Perfectly fine for computational or astronomical applications, but not for human ones.

It is even worse than measuring speed limits in c. Or the area of nation states in fractions of the surface area of Enceladus. Even those can be good benchmarks, even if they are... clunky.

Preferably, no mythology this time around.

Preferably, don't use the UNIX epoch. I dislike UNIX.

(or another unit that follows from a basic physical fact about the universe)

Seconds are derived from the day. If I were choosing a time unit based on a universal physical phenomena, I would not choose something as arbitrary as the second.

It's just that the SI defines the second based on a specific physical phenomenon, it isn't derived from it.

 

[elephantium]

It is without reference to anything. Dogs are wired to think in terms of days and months and years.

This should illustrate the problem with your logic.

That's not to say that switching wholesale to a new time system would be a realistic notion; most humans are very strongly trained in the second-minute-hour day-month-year time system. I'd give a new time system about a 50% chance of catching on ... about 50 years after the United States completes the changeover to metric that was supposedly in the works about 30 years ago. :lol:

 

[Cras]

You flat out cannot get rid of the day, the week, the month, or the year. This is how human beings have marked history for thousands of years, and to throw that away for a misguided attempt to keep the clock in check with some sort of cosmic constant is a hopeless, if not useless endeavour.

And considering time is relative to the observer, it makes perfect sense to keep track of time by the cycles of the moon and the sun.

 

[T.Neo]

This should illustrate the problem with your logic.

Why? What is wrong with dogs? :huh:

That's not to say that switching wholesale to a new time system would be a realistic notion; most humans are very strongly trained in the second-minute-hour day-month-year time system.

It isn't about training, it's about ingrained biological settings. I'm primarily talking about the day here, hours and minutes and seconds are less important.

 

[Jarvitä]

The problem is that the "epoch plus seconds" timekeeping system is absolutely and utterly meaningless in the real world, no matter how "science-y" it sounds.

Seriously. I started typing this post at 1 320 506 964. What?

That 'time' makes absolutely no sense to me. It is just a random number. It might as well be 74 088. Or 761 390. Or 555 614 042.

Huh?

Yes, and "Four twenty-fourths of an earth day, fifty .000694-parts of an Earth-day, and twenty .000011574074074-parts of an Earth-day after solar zenith on Earth, on the twenty-fifth day in the month of Gaius Julius Caesar, in the year of our Lord 2485" will sound equally meaningless to people living in extrasolar colonies or as uploads in an ellipsoid of computronium hurtling through intergalactic space.

Given enough diversity, any reference is meaningless. Might as well pick one that's equally meaningless for everyone, and let local cultures design their own systems that are based on it and easily convertible.

It is without reference to anything. Humans are wired to think in terms of days and months and years.

People living on the surface of Earth are raised to think in terms of days and months and years.

Preferably, don't use the UNIX epoch. I dislike UNIX.

The epoch is negotiable. How about the day the first human object reached space? Although I can imagine many would be opposed to enshrining the V2 like that.

Seconds are derived from the day. If I were choosing a time unit based on a universal physical phenomena, I would not choose something as arbitrary as the second.

The base unit is, likewise, negotiable. However, the second is a pretty good choice, it's small enough for precision, and large enough so it doesn't get unwieldy even with long-term events. You could use Planck time, but you'd have to invent new SI prefixes up to 10^50 and perhaps above to be able to describe common events in human activities.

That's not to say that switching wholesale to a new time system would be a realistic notion

Completely unrealistic and undoable. Doesn't prevent us from hypothesizing about a marginally more sane world, however.

 

[T.Neo]

Yes, and "Four twenty-fourths of an earth day, fifty .000694-parts of an Earth-day, and twenty .000011574074074-parts of an Earth-day after solar zenith on Earth, on the twenty-fifth day in the month of Gaius Julius Caesar, in the year of our Lord 2485" will sound equally meaningless to people living in extrasolar colonies.

Firstly, bad example. You purposefully made it as clunky and convoluted as possible, which is really annoying.

Secondly, I said nothing about minutes or hours or seconds or calendars, but about natural cycles that are intrinsically important to humans, compared to epoch+ unit time dates, which fail to address that importance totally.

Thirdly, while extrasolar colonies are a fantasy that you seem to have an affinity for, none currently exist and they sadly seem quite unlikely. Therefore timekeeping in real and relevant situations is a more important matter.

People living on the surface of Earth are raised to think in terms of days and months and years.

Wrong. It is of intrinsic importance due to our evolutionary history. Days govern our daily lives, the menstrual cycle (and also oppurtunities for hunting and waiting for tides in some cultures) is close to the lunar month, and years define seasons which are equally important.

Ok; so maybe the last two are less relevant. But to put things into perspective, I was taught to go to bed at 20:00 and wake up at 07:00 when I was young. The times at which I go to sleep and wake up at now are nothing like that, but I still adhere to a roughly 24 hour cycle.

How about the day the first human object reached space?

Sounds like an annoying science fiction cliche.

You could use Planck time, but you'd have to invent new SI prefixes up to 10^50 and perhaps above to be able to describe common events in human activities.

Why bother? You've just thrown human relevance out the window, so you might as well do it entirely.

Doesn't prevent us from hypothesizing about a marginally more sane world, however.

Why is it not "sane"? Because you said so? Because you personally dislike the idea?

Our current time system works. It's relevant, and it does its job. And it may be a bit clunky, but that does not make it un-sane.

Dislike it all you wish. I still don't get the point of why we still have minutes and hours...

 

[elephantium]

It is of intrinsic importance due to our evolutionary history. Days govern our daily lives, the menstrual cycle (and also oppurtunities for hunting and waiting for tides in some cultures) is close to the lunar month, and years define seasons which are equally important.

Can you prove this? TBH, it sounds more like something you've made up rather than something intrinsic to the human body.

 

[FADEC]

Yes, our current system is inaccurate anyway. A day hasn't 24 hours, and a year hasn't 365 days. And the year or the reference we use is nonsense also (I'm sceptical if that certain person called Jesus even did exist). But: it works perfectly for a lot of humans for more than 2000 years. The only thing I would like to se abandoned is the summer/standard time change because it completely makes no sense to me.

 

[T.Neo]

Can you prove this? TBH, it sounds more like something you've made up rather than something intrinsic to the human body.

Oh really? I made it up? :dry:

Kindly explain why I don't go to sleep every week or so, for about a week, and then wake up, for about a week, and then go back to sleep again, without talking to flying lobsters at the end of the waking period...

A day hasn't 24 hours, and a year hasn't 365 days.

Close enough.

And the year or the reference we use is nonsense

Not necessarily "nonsense". Also, people disliking it is not a reason to get rid of it.

 

[Cras]

@elephantium

I would like to know why a method of keeping time that is totally arbitrary (due to its source of time zero of the epoch), is more sane and acceptable than one that makrs the moon's cycle, the seasonal cycle, or Earth's orbit around the sun? Not to mention throws away thousands of years of culture, tradition, and just flat out human experience?

And you talk about plank time so surely you understand then that using an Earth calender on a far away planet makes utterly no sense, even for a place such as Mars. The concept of now and what now consists of dramatically changes as the difference in speed and distance changes, that it makes the idea of formulating a calender and time system that is compatible for here and a far away space colony a hopeless exercise. This is Special Relativity 101.