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Metric Time

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Re: Metric Time

#241

Post by Kon-Peki »

eps wrote: post #108
toxik wrote: post #74

I love how the example is super confusing. You sleep 3.33… metric hours. You fall asleep 9:50 metric time. You'd think we can just interchange the . and : so you should wake up 12:83…, or 2:83… the next day. But no, it's apparently 2:75 metric time. Why? Also nice how they IMMEDIATELY ran into a continuing fraction 1/3, which is exactly the point of the 60-minute hour, 24-hour day, or 360-degree circle: lots of facto…

Come to think of it, being able to cleanly divide a minute or an hour into 2, 3, 4, 5 and 6 equal parts is pretty damn handy.

> cleanly divide a minute or an hour into 2, 3, 4, 5 and 6 equal parts

Lawyers bill their time in tenths of an hour - exactly 6 minute increments.

Re: Metric Time

#243

Post by downvotetruth »

ithkuil wrote: post #68
downvotetruth wrote: post #10

Earlier quoted context omitted.

FTFY: English does not need a second conflicting definition for the second.

there is no multiple definitions going on: what happened is an _elision_. The actual word is "second minute" (as opposed to the "first minute"). Most languages have by now elided "first" from "first minute" resulting in the "minute" as we know it today, and elided "minute" from "second minute" resulting in the "second" as we know it today. i.e. "second" literally means "the one that comes after the first", but is imp…

> subdivision of the small unit of time

Part of the point is the "second" definition based on a subdivision is no longer the SI second. You are right about the elision, but in the context of the time most people are now eliding System International ("SI") from the beginning rather than "minute" at the end.

"Seconds were once derived by dividing astronomical events into smaller parts, with the International System of Units (SI) at one time defining the second as a fraction of the mean solar day and later relating it to the tropical year. This changed in 1967, when the second was redefined as the duration of 9,192,631,770 energy transitions of the cesium atom."

https://www.scientificamerican.com/article/experts-time-divi...

Re: Metric Time

#244

Post by kybernetikos »

rimliu wrote: post #204
kybernetikos wrote: post #151

I'm a big fan of decimal time (or French Revolutionary Time as it's sometimes called). I made my own version a few years back: https://kybernetikos.github.io/UIT/ My version also removes timezones. The numeric time is the same whereever you are in the world, but the display changes based on your location so that local solar midday is straight up on the clock face and local solar midnight is straight down on the clock…

Simple and useless. You can have any system you want for your personal use, but clocks and calendars are for colaboration. It's nice that you have day and night hours on the clock where you are. No you will travel a few thousand kilometers. You know your decimal time you get there, do you know whether it will be daytime or nighttime? You get there, and it is winter and the dark time is 3x of the daytime. Have you got…

In the full version there is an unrolled map of the world down the side with the terminator drawn on which solves all those concerns.

Even if those problems were harder to solve its far more valuable to have a single time for your meeting than multiple times (depending on the time zones and savings time of the participants). The pain of organising international meetings was one of the reasons I did this.

Re: Metric Time

#245

Post by kybernetikos »

xattt wrote: post #188
kybernetikos wrote: post #174

Earlier quoted context omitted.

No because its a humane rather than scientific system. Day lengths in a scientific time vary, but in this system the hours are defined to be 10ths of a solar day so they vary as the day varies. Scientific measurement should be done with a different system. I'd suggest something based on the speed of light.

> … but in this system the hours are defined to be 10ths of a solar day so they vary as the day varies. This is reasonable and not unsafe at all, particularly when it comes to timing things like exposure time with patients receiving radiation therapy. However, we will be left wondering why treatment in the summer is more effective that treatment in the winter. Must be the nice weather.

Firstly the time variance we're talking about is small and will only matter when milliseconds matter, secondly I addressed this - for scientific measures and scenarios where milliseconds matter a different time unit should be used.

If you want to prioritise ease of moving between the two systems, I'd suggest a normalised version of the new second. If you want to prioritise science, then something that makes a nice round number when giving the speed of light would be nice. If you want to prioritise ease of adoption, just keep the current SI second, just stop using it to measure times of day.

Either way the symbol for writing it should be different.

Re: Metric Time

#246

Post by somestag »

rplnt wrote: post #229
prometheus76 wrote: post #177

Earlier quoted context omitted.

Now apply the same logic to measurement, and you'll see why it's so handy to use a dozenal foot for fabricating things.

Is 1/3 (1/6) such an important concept? 1/2 (1/4) is natural in metric. I would think a bigger benefit is that you can drop up and down without any math depending on the precision you need. Or use decimals, no math involved either, since it's the same thing.

Yes, 1/3 and 1/6 are quite important. Do enough making and you will run into those fractions plenty. It just turns out that in practice, as you say, easy unit conversions outweigh the benefit of clean division. Metric's important benefit is that it's a consistent base, not that it's specifically base-10.

And now that we use computers for a lot of measurement, those infinite decimals aren't as big of a deal. (Well, most of the time, anyway. Representation of infinite fractions famously creates some programming problems. But I mean for the user making the measurement.)

Base-10 is easy to learn since it's the same we use for counting, but I think there's an interesting argument to be made that purely from a science/engineering/making perspective it would be better to use a consistent base-12 measurement system.

Re: Metric Time

#247

Post by ChilledTonic »

kybernetikos wrote: post #151

I'm a big fan of decimal time (or French Revolutionary Time as it's sometimes called). I made my own version a few years back: https://kybernetikos.github.io/UIT/ My version also removes timezones. The numeric time is the same whereever you are in the world, but the display changes based on your location so that local solar midday is straight up on the clock face and local solar midnight is straight down on the clock…

I also use Decimal Time and the French Republican Calendar as my default calendar and time method. The mental math to convert back to "standard" time and date is very easy once you get the hang of it, and I think it's good practice to not take for granted systems we consider "standard" such as time.

For more on the philosophy of this, I highly recommend Jenny Odell's Book, Saving Time. Note that she doesn't talk about the revolutionary calendar in it (to my memory) but touches on a lot of the realities of time and clocks themselves.

https://en.wikipedia.org/wiki/French_Republican_calendar

Re: Metric Time

#248

Post by bre1010 »

abeppu wrote: post #19

Does this short page describing a base-10 way of dividing time actually fail to be internally consistent for the few sentences of text describing it? > A standard hour is broken into 60 minutes. There are 2.4 standard hours in 1 metric hour. > A metric minute is broken into 100 seconds. > A standard minute has 60 seconds. There are 2.4 standard minutes in 1 metric minute. No, a standard minute is 1/1440 of a day, and…

I was very confused by this too and finally realized the mistake. The chain of logic went like this:

> There are 2.4 standard hours in 1 metric hour > Therefore there are 240 standard minutes in 1 metric hour > Then divide by 100 to get 2.4 standard minutes per metric minute

Except there aren't 240 standard minutes in 1 metric hour. There's 2.4 * 60 = 144. That the author of the page couldn't keep the conversions straight does not bode well if we were to switch as a society...

Re: Metric Time

#249

Post by pif »

acka wrote: post #220
pif wrote: post #207

Earlier quoted context omitted.

Is this a common joke?

https://en.wiktionary.org/wiki/freedom_units

Thanks, I've learnt something today.

Just out of curiosity: is it just a joke, or is there an idiocy behind, such as Sovereign Citizen or similar?

Re: Metric Time

#250

Post by jstanley »

Karellen wrote: post #120
tomtomtom777 wrote: post #118

Earlier quoted context omitted.

Exactly. The exact amount of sleep needed on average is almost certainly an irrational number. (Because almost every number is irrational)

Are you sure? Isn't the average calculated by dividing by n , an integer? Edit: I mean, you're right that nearly every number is irrational. But I think averages are going to be some of the tiny fraction of numbers that aren't.

Actually averages are even more likely to be irrational than ordinary numbers.

It only takes a single irrational input to make the average irrational.

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