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Metric Time

metric-time.com

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Re: Metric Time

#91

Post by L3viathan »

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…

> 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 factors.

While I agree in principle, this example is not evidence of it. It's not like we measured the amount of sleep needed and it's precisely 8 hours. A more reasonable thing to say would be: You need to sleep for 3.5 metric hours.

Re: Metric Time

#92

Post by michaelhoney »

blurbleblurble wrote: post #39
tcmb wrote: post #31

Earlier quoted context omitted.

True. And having 7 days per week is majorly impractical, also for reasons of divisibility. With 7 being prime, it's impossible to do things every other day or every three days without being left with a remainder.

But at least 7 days per week resonates approximately with the lunar orbit.

clearly we need to reposition the moon

Re: Metric Time

#93

Post by II2II »

shrumm wrote: post #26

This was a fascinating read for a totally unexpected reason. I’ve spent most of my life in countries where the metric system is used for distance, weight, temperature etc. This year I’ve had to travel a lot to the US for work and found the constant mental conversions a PITA. I kept wondering why people keep holding out against such an obviously easier system. Then I read this article about 8 hours of sleep would be 3…

Yeah, too much of our society is based upon 24 hour time.

The transition is also unlikely to have many benefits. Unlike most of the other units of measure, the everyday conversions are fuzzy. The only exception I've seen is when payroll bean counters expect minute precision converted to decimal hours, which is a pain! Everything in science and engineering tends to be maintained in seconds, which is decimalized anyway so there is no benefit there.

I don't see "metric time" making any headway, particularly since something like universal time would be much more beneficial yet hasn't gained traction.

Re: Metric Time

#94

Post by gpderetta »

dehrmann wrote: post #21
twelvechairs wrote: post #3

> Working with base-10 numbers is so much easier than trying to think in base-60, base-12, and base-24. > To get a good night sleep (8 standard hours) you'd sleep for 3.33 metric hours. Quote 2 seems to clearly contradict quote 1. 60 is great as it divides into 2,3,4 and 5. That's a feature not a bug

Yeah, base 12 is the most practical for divisibility. 60 is good, but it's too big to conceptualize. >> Working with base-10 numbers is so much easier I mean, every base is base 10.

There are 10 kinds of people in the world...

Re: Metric Time

#96

Post by pavlov »

This is exactly the decimal time system used in France during the brief period of the post-revolutionary established First Republic, 1794 to 1800.

Although the metric system originated at the same time, it's important to note that the French Republican decimal second isn't the same as the one used by international metric system (SI) that we ended up with. So calling this "metric time" is quite misleading.

The decimal second is shorter than the standard one because there are 100,000 decimal seconds in a day vs. 86,400 SI seconds in a day.

(If you're a rich antiques collector, a late 18th century French decimal clock might be a very interesting object. My understanding is that they are rare because their active use was so short and most clocks were repurposed to standard ones.)

Re: Metric Time

#97

Post by pmontra »

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…

I didn't check the details of that metric time system but there would be no problem living a 10 hours day with 100 minutes hours and 100 seconds minutes. The second would be defined with a different number of "cycles of the radiation produced by the transition between two levels of the cesium-133 atom" and that's all. Instead of rounding our lives at "our" quarters of hours or ten minutes, five minutes marks we would round to the metric quarters of hours, maybe eights of hours (we could have found a name for that, like for coins) etc, and nobody would notice because that would be what we are born with.

Similarly, people buy 50 cm x 70 cm frames in metric countries and 20" x 30" frames in the USA. Nobody thinks about that except frame factories in China, that have to cut them in two sizes.

Re: Metric Time

#98

Post by pmontra »

INTPenis wrote: post #47
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 still don't understand how a metric day matches up with a standard day. I flunked 10th grade math and later dropped out, my brain is having a stroke just reading those graphs. I reverted back to seconds, which is how I used to use Unix timestamps when I first started with computers. But one day would have 100000 seconds, compared to 86400 seconds in standard time, so how can they both measure a day?

A day is a day, Earth rotation defines it. What we can do is decide how long a second is and tweak it to make a day 100k seconds long or 86.4k ones.

Re: Metric Time

#99

Post by pipo234 »

Entalpi wrote: post #83
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…

Its like we have built our entire lives around another time system! /s You get similar problems converting between Freedom degrees and Celsius. Its just what people have built an understanding of.

To quote yet another time format: NTP 64-bit timestamp format (rfc8877), which is 32 bits seconds since epoch + 32 bits fixed point second fractions. (Outside of Network Time Protocol, you'll find this baby for instance in ISOBMFF ProducerReferenceTimeBox(prft)).

Here seconds are just 1/(24*60*60) of a day as expected, but the base 2 fixed point part, where a tick "is roughly equal to 233 picoseconds" makes you want to pull your hairs out if you just want to accurately express milliseconds. (Similarly for other timescales frequently used in media processing, like 90kHz, 25, 60 or 29.97)

The answer to all this is of course: hand waving — "you don't need that". Your time can be perfectly accurate in itself (ie. an accurate discrete sample of continuous time), even if no accurate conversion exists to some other time system.

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