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Metric Time

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Re: Metric Time

#181

Post by vidarh »

dghughes wrote: post #143
funcDropShadow wrote: post #106

Earlier quoted context omitted.

No "metric" units means they are derived from the meter. Originally, most units in the SI systems were derived from the meter.

And based on a 1,000 (kilo) of something so 1 metre 1,000g (kilometre), 1 gram 1,000g (kilogram). You can have centimetres but that not in the spirit of the metric system really. Maybe we need a cron for an hour or a day? 1,000 crons for an hour sounds better than millicrons by breaking up a day if it was 1 cron.

> You can have centimetres but that not in the spirit of the metric system really.

"Centi" is an SI prefix just as much as "kilo" is, and has been part of the metric system since 1795 just like "kilo". I don't see how it's "not in the spirit" of the metric system. It also fits in neatly in that 1cm^3 of water is roughly 1 gram (the original provisional definition of gram was 1cm^3 of water at the melting point of ice; the current definition is more precise), and so 10cm^3 of water is roughly 1 liter.

The SI system has prefixes going up and down one power of 10 up to 10^3 and down to 10^-3, and then in steps of 10^3. They're all equally part of the system; some are just more common in some contexts that others (e.g. we use hectograms but rarely hectolitres, and decilitres but rarely decimetres, and centimetres and centilitres but rarely centigrams) depending on what happens to be convenient.

E.g. kilo(10^3), hecto(10^2), deca(10^1), deci(10^-1), centi(10^-2), milli(10^3), but then mega (10^6) and micro(10^-6) are the next steps.

Re: Metric Time

#183

Post by evrydayhustling »

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…

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.

Re: Metric Time

#184

Post by red_trumpet »

ReleaseCandidat wrote: post #158
red_trumpet wrote: post #135

Earlier quoted context omitted.

Only if you take an average of rational numbers. Like e/2 is still irrational.

While in theory you could measure sleeping time in fractions of 2 pi, I'd guess that you're using rational numbers in the actual calculation anyways.

Why would sleeping time be a fraction of 2pi?

> I'd guess that you're using rational numbers in the actual calculation anyways.

Well, actually one uses floating point arithmetic, which isn't rational numbers either (as shown by the classic example a = 1/3, b = 3*a, then b != a)

Re: Metric Time

#185

Post by nycdotnet »

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.

This is the same reason a point is 1/72 on an inch - many factors make convenient typesetting.

Re: Metric Time

#186

Post by BoxOfRain »

scroot wrote: post #156
shiroiuma wrote: post #85

Earlier quoted context omitted.

>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.

the UK pint is bigger than the US pint. Know this before visiting and it could just save you a hangover.

The now relatively uncommon UK gallon is the volume occupied by ten lbs of water in the same way a litre of water weighs a kilogram. Not only are the pints bigger there’s also twenty ounces (also rarely used now) in them which means a fluid ounce of water weighs by definition an ounce in the imperial system.

Re: Metric Time

#187

Post by willis936 »

kybernetikos wrote: post #162
willis936 wrote: post #145

Earlier quoted context omitted.

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.

Decimal seconds are slightly shorter than normal seconds, so times that use seconds are more precise. The other fun thing is that decimal time doesn't really need names for the levels, it's just numbers of significant figures so if you only want to give the first digit of the seconds that works too.

It's less precision for a given number of symbols. Fewer usable factors mean you can only reasonably divide up segments of time into larger, less precise chunks.

Re: Metric Time

#188

Post by xattt »

kybernetikos wrote: post #174
paulryanrogers wrote: post #172

Earlier quoted context omitted.

Is there a quarter day at the end of the year?

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.

Re: Metric Time

#189

Post by bloopernova »

Another excuse to share the wonderful Unix epoch clock: https://retr0.id/stuff/2038/

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.

Re: Metric Time

#190

Post by JR1427 »

s0teri0s wrote: post #152
JR1427 wrote: post #129

Earlier quoted context omitted.

Why is having fewer time zones a good thing? Wouldn't this actually be confusing, because things would have to be happening at different local times depending on where you are in the time zone?

I wasn't really advocating for it, I just think if we were crazy enough to adopt this time system, 10 time zones would also be a necessary adjustment.

Ah, I see. That makes sense! Although not all timezones are +/- an integer number of hours.
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