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 face. Day and night hours are drawn on the face.
I used to have it attach to your google calendar and draw meetings onto the clock face too, but I think in the last 11 years the google calendar api has changed and I haven't updated it.
Obviously once you have metric time, you need a metric week too, so I have new week days: nullday, unday, duoday, triday, quadday, hexday heptday, octday and nonday. There's no need for months anymore, I just number the weeks. Of course 28th Quadday is the 285th day in the year, as the first day is 0th Nullday. Fixing the number of weeks in a year to a round number is left as an exercise for the reader.
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.
I am curious which leap day system you use for the French Republican calendar. Most popular versions of the calendar I see floating around just use the Gregorian leap year system, which I don't like because it yields the wrong results in the year the calendar was in use. Yet, I don't see mental math as a viable option when using the original date-of-equinox method used during the revolution.
About the non timezone version but skates over the fact that he doesn't know the answer in the timezone version either. He says "Google tells me..." well sure, if you're allowed to use Google you could just have easily have asked "what are typical daylight/waking hours in x location?" This is much better anyway since in some countries culturally you siesta in the early afternoon (don't call please) and stay up later.
Anyway there is something of a genuine problem here (although I don't consider it serious) and I'd solve it by drawing the world on the side of the clock and allowing you to rotate the face by selecting a place on the map.
The arguments against removing timezones apply to adding timezones - it just depends on what you're used to or which type of conversion you find easier. The arguments in this oft-circulated article really fall flat.
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 any idea when anything opens and closes?
And why have weeks if you don't have months. How about just numbered days?
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.
It's been explicitly highlighted to me before that the calendar in the French Revolution is called the French Republican Clendar and not the French Revolutionary Calendar, so I'd assum the same is true and it would be French Republican Time
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.
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 factors.
> 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.
I don't really care how much sleep I get as long as it's enough. I care greatly when the bus leaves and when my meetings are. Anything that hopes to replace a clock had better be adding precision rather than removing it.
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.
Nobody questions the logical consistency of the system, I think.
Presently, we use 24-hour time (AM/PM or otherwise), so the loss in precision is enormous going from 24 to 10.
Think about it.
A tenth of a standard hour is 6 standard minutes.
A tenth of a metric hour is 144 standard minutes, more than two standard hours.
A hundredth of a standard hour is 36 standard seconds, or half a minute. It is in the context of hours a negligible amount of time.
A hundredth of a metric hour is 14.4 standard minutes! Imagine being 0.01 metric hours late for a meeting.
So everywhere you now have to specify time to two decimal places /at least/, three to have sub-standard-minute precision.
Layer on top of this the fact that the new system has significantly fewer distinct prime factors, so you quickly run into continuing fractions. Disaster.
Instead of changing the definition of second, it might make sense to separate day-time from scientific time. Decimal hours and minutes would be normal time keeping. If needed more accuracy, then would switch use centi-minute for casual use or second for scientific use.
One nice feature is that the day-time would be different on other planets. There would Mars-day and Mars-hour. But the second would be the same.
An hour is just an another name for a deciturn, or a deciday.
Tau is not a good unit for angles in general, unless you have circles, or you need lengths of circumferences somewhere. (You want to paint your clock and calculate the amount of paint, or something.) Turn is the natural angle unit. And since the earth rotates 1 turn/day, the amount of turns is the same as the amount of days.
Metric time is about factors too, but it prioritizes the factors that simplify the comparison across (literally) many orders of magnitude. This is way less helpful for everyday life because we usually only reason within 2-3 orders of magnitude, but we deal with tons of harmonic subcycles that the 24h clock makes easy.
For a fun, a more justified usage of metric time, check out Vernor Vinge's "A Deepness in the Sky" (also IMO one of the best sci-fi novels of all time). A spacefaring humanity that stretches their life across journeys and projects that span centuries, and which has to artificially produce their own daily cycles, gets a lot more value out of metric time.
Came here to mention/contrast Vinge's metric time with with my (quick, approximate) understanding of this approach...
The problem with this approach is it attempts to "redefine" hours and minutes... part of what I liked in Vinge's/Deepness' approach was, it ignored all that and just talked about seconds in standard exponential scientific notation... it makes a lot more sense in space though, where there's no need/logic to connecting or synchronize to a specific solar cycle, so they just think/talk in kilo-seconds (about 40 mins) and mega-seconds (about 11.6 days)... or at least those are the two I recall them using enough that I got semi-used to thinking in them while reading the book... I had to convert, but I didn't have to redefine any existing unit or remember/remind myself which meaning of hour/minute they're using, because nothing changed.
> 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?
You can, they just messed up the example by unnecessarily rounding off the times. The night from 9:50 till 2:75 metric time only lasts 3.25 metric hours, or 7h48m in standard time; less than the 8 standard hours they started with.
You know what other measuring system is based around highly composable numbers?
It's not metric. It's the imperial system. Halves, thirds, quarters are all neat numbers. It does get a little weird because we only use feet, yards, and miles today, but there is a progression from inch to mile that all make sense to some degree.
Similarly with volumes. You can get from teaspoon to gallon without having to worry about any weird decimals.
The only thing metric really has going for it is uniformity of conversion.
People shit on it, but the imperial system is not actually that horrible.
I disagree, it’s not equal but different. The French famously tried to switch to a decimal system for angles before, but failed in no small part because of the relatively few unique prime factors. Being able to divide evenly by three turns out to be more important than five.
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.
Yes, a very confusing error.
The metric time is the SI time (24h 60m 60s).
The decimal time is base 10.
French tried to get it used during the revolution and it did not work. Its the only unit that resisted decimalization, with a couple others ones in a handful of countries still using something called « imperial units ».
Another similar thought experiment is binary clocks which I remember using to get use to read in base 2. [1]
Weekly clocks are also a good way to change perspective on time. [2]
Both are fun to use, especially with other people if you manage to get them to experiment with you. Both have the avantage of avoiding any confusion with SI time.
>with a couple others ones in a handful of countries still using something called « imperial units ».
The only country I know of offhand that uses "imperial units" is the UK.
There's a different, but similar (and sometimes overlapping) system called "US Customary Units" that's used in the US. Imperial pints and gallons are NOT the same as US pints and gallons.
Metric time is a better name, since it states that this time comes naturally from our common metric system, and something is very very off that we don't use it.
Watch face has 4 hands, one for each pair of characters in the hex representation of the current unix time.
Being hex, it kinda makes it easier to understand for me in that the "minute" is 255 seconds. The next chunk of time is 65,025 seconds or about 18 hours. Then comes 16,581,375 seconds, which is almost 192 days.
Actually the minute is 256 seconds (2^8). The next chunk of time is 65536 (2^16). Then comes 16777216 (2^24). The whole clock rolls over at 4294967296 (2^32).
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...
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?
My favorite is traditional Japanese time. Breaks day and night into 6 equal time periods each, and adjusts them as the seasons change. I made a Sahku Dokei (19th century Japanese pillar clock) simulator to play with it.
In a way, China kind of has something like the Swatch gimmick for real. There's just one time zone in the whole country (which is roughly the size of the Continental US). This has benefits (easy to coordinate video conferences in different cities) and drawbacks (the official time is far off from what the sun would indicate in much of China).
It only works because the overwhelming majority of the population and all of the political and economic power lies on the east coast of China in a single time zone. I doubt that the people in Urumqi are happy to have the sun rise at 10 am, and I doubt that anyone cares about their opinions.
I think the idea is that for most human uses of time we don't specify start or end times to a precision of more than about 5 minutes. Stuff like train timetables you might want to go down to about a minute. So one could argue that we have at least 60 times the resolution we really need for day-to-day use.
If you absolutely need more precision (accurate timestamping) then decimals are available.
"way less precise" ? There are only 1440 minutes in a day, so a beat is 1 minute and 26.4 seconds, precise enough. And then, if you you want more precision, like we use seconds for minutes, you can divide a beat by 100 (@500.12), not less inconvenient than using seconds.
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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 face. Day and night hours are drawn on the face.
I used to have it attach to your google calendar and draw meetings onto the clock face too, but I think in the last 11 years the google calendar api has changed and I haven't updated it.
Obviously once you have metric time, you need a metric week too, so I have new week days: nullday, unday, duoday, triday, quadday, hexday heptday, octday and nonday. There's no need for months anymore, I just number the weeks. Of course 28th Quadday is the 285th day in the year, as the first day is 0th Nullday. Fixing the number of weeks in a year to a round number is left as an exercise for the reader.
Time and date maths becomes very simple.
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
(The article is still relevant with metric time/weeks)
> Does that mean I can call him? I don't know.
About the non timezone version but skates over the fact that he doesn't know the answer in the timezone version either. He says "Google tells me..." well sure, if you're allowed to use Google you could just have easily have asked "what are typical daylight/waking hours in x location?" This is much better anyway since in some countries culturally you siesta in the early afternoon (don't call please) and stay up later.
Anyway there is something of a genuine problem here (although I don't consider it serious) and I'd solve it by drawing the world on the side of the clock and allowing you to rotate the face by selecting a place on the map.
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.
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 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.
"Eight hours for work, eight hours for rest and eight hours for what you will."
Lawyers bill their time in tenths of an hour - exactly 6 minute increments.
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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.
Presently, we use 24-hour time (AM/PM or otherwise), so the loss in precision is enormous going from 24 to 10.
Think about it.
A tenth of a standard hour is 6 standard minutes.
A tenth of a metric hour is 144 standard minutes, more than two standard hours.
A hundredth of a standard hour is 36 standard seconds, or half a minute. It is in the context of hours a negligible amount of time.
A hundredth of a metric hour is 14.4 standard minutes! Imagine being 0.01 metric hours late for a meeting.
So everywhere you now have to specify time to two decimal places /at least/, three to have sub-standard-minute precision.
Layer on top of this the fact that the new system has significantly fewer distinct prime factors, so you quickly run into continuing fractions. Disaster.
One nice feature is that the day-time would be different on other planets. There would Mars-day and Mars-hour. But the second would be the same.
Tau is not a good unit for angles in general, unless you have circles, or you need lengths of circumferences somewhere. (You want to paint your clock and calculate the amount of paint, or something.) Turn is the natural angle unit. And since the earth rotates 1 turn/day, the amount of turns is the same as the amount of days.
For a fun, a more justified usage of metric time, check out Vernor Vinge's "A Deepness in the Sky" (also IMO one of the best sci-fi novels of all time). A spacefaring humanity that stretches their life across journeys and projects that span centuries, and which has to artificially produce their own daily cycles, gets a lot more value out of metric time.
The problem with this approach is it attempts to "redefine" hours and minutes... part of what I liked in Vinge's/Deepness' approach was, it ignored all that and just talked about seconds in standard exponential scientific notation... it makes a lot more sense in space though, where there's no need/logic to connecting or synchronize to a specific solar cycle, so they just think/talk in kilo-seconds (about 40 mins) and mega-seconds (about 11.6 days)... or at least those are the two I recall them using enough that I got semi-used to thinking in them while reading the book... I had to convert, but I didn't have to redefine any existing unit or remember/remind myself which meaning of hour/minute they're using, because nothing changed.
A while since I read it, but in short I disliked the characters which I could not symphatize with.
The dog story (which started out great) and the humor wasn't me either.
> But no, it's apparently 2:75 metric time. Why?
You can, they just messed up the example by unnecessarily rounding off the times. The night from 9:50 till 2:75 metric time only lasts 3.25 metric hours, or 7h48m in standard time; less than the 8 standard hours they started with.
It's not metric. It's the imperial system. Halves, thirds, quarters are all neat numbers. It does get a little weird because we only use feet, yards, and miles today, but there is a progression from inch to mile that all make sense to some degree.
Similarly with volumes. You can get from teaspoon to gallon without having to worry about any weird decimals.
The only thing metric really has going for it is uniformity of conversion.
People shit on it, but the imperial system is not actually that horrible.
You get similar problems converting between Freedom degrees and Celsius. Its just what people have built an understanding of.
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.
We should do something about that.
https://en.wikipedia.org/wiki/Metric_time
Another similar thought experiment is binary clocks which I remember using to get use to read in base 2. [1]
Weekly clocks are also a good way to change perspective on time. [2]
Both are fun to use, especially with other people if you manage to get them to experiment with you. Both have the avantage of avoiding any confusion with SI time.
[1]: https://en.m.wikipedia.org/wiki/Binary_clock [2]: https://dayclocks.com/products/classic-oak
The only country I know of offhand that uses "imperial units" is the UK.
There's a different, but similar (and sometimes overlapping) system called "US Customary Units" that's used in the US. Imperial pints and gallons are NOT the same as US pints and gallons.
[0] https://en.wikipedia.org/wiki/Decimal_time
Watch face has 4 hands, one for each pair of characters in the hex representation of the current unix time.
Being hex, it kinda makes it easier to understand for me in that the "minute" is 255 seconds. The next chunk of time is 65,025 seconds or about 18 hours. Then comes 16,581,375 seconds, which is almost 192 days.
> 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 a metric minute is 1/1000 of a day. There are 1.44 standard minutes in a metric minute.
> 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...
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?
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Each milliday is about 90 seconds.
And a microday is slightly shorter than a second.
But, sadly, this revolution won't occur until after I'm elected God-Emperor of Mars, so it is all rather academic.
And you'll have to make all your intervals slightly longer, due to Mars' solar day being 24h39m35s by standard Earth time.
When following SI, a microday would be 0.0864 (or approximately 0.1 second) which doesn't seem to be a very practical unit.
You have my vote!
https://en.wikipedia.org/wiki/Swatch_Internet_Time
https://www.tdcmotorsports.com/clock/
Dividing one day into just 1000 units is way less precise unless one uses decimals, in which case it's just plain inconvenient.
If you absolutely need more precision (accurate timestamping) then decimals are available.
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