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Metric Time

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Re: Metric Time

#251

Post by kybernetikos »

willis936 wrote: post #187
kybernetikos wrote: post #162

Earlier quoted context omitted.

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.

This is far from the truth. The closest time before midnight you can conveniently represent in the current time system is 23:59:59 which is six symbols for a standard second before midnight.

In decimal time the closest time before midnight you can conveniently represent would be .9:99:99 which is noticeably closer (0.163 of a second closer) to midnight and uses only 5 symbols.

This should not be surprising - our current system is very inefficient in its use of digits.

Re: Metric Time

#252

Post by js2 »

have_faith wrote: post #148
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.

We use a mix of everything in the UK, although metric is common in many areas where it matters.

As a US observer, my favorite UK unit is the stone.

https://en.wikipedia.org/wiki/Stone_(unit)

Re: Metric Time

#253

Post by kybernetikos »

worthless-trash wrote: post #237
lesuorac wrote: post #215

Earlier quoted context omitted.

Is that how you program things? I recommend using as little as date/day mechanics as you can get away with. Instead using a monotonic durations as much as you can [1]. If you continue to program with date/day mechanics you'll run into plenty of issues when users cross timezones or just set the time on their phone to a different one. [1]: https://en.wikipedia.org/wiki/Unix_time

My favorite things is when you connect to cell towers that have DST in one state, and not in another, the cell phone getting the time/date from "the network".

Yes, getting rid of the various savings time is important too.

All the people pointing out the (genuine) problems with decimal time seem to be weirdly tolerant of the problems with our current system, which has much worse problems.

If you imagine the reverse situation, where society uses a decimal time, and some people are arguing we should switch to this system because despite all the things it makes worse and harder, it divides better and the numbers map somewhat (although imperfectly) to the actual time-of-day in various locales and (even less perfectly) to the kinds of things people might be doing at that time, everyone would think they were crazy.

Re: Metric Time

#254

Post by downvotetruth »

reliablereason wrote: post #213
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)

It’s almost certainly a rational number as activity in the body is finite. There will be an exact point at which a certain molecule has interacted with another molecule marking the exact point of perfect sleep. Averaging many rational numbers can’t get you an irrational number. Also it is invalid to compare infinite series like you do in your paracentesis argument, there are infinitely many irrational numbers and inf…

> will be an exact point at which a certain molecule has interacted with another molecule marking the exact point of perfect sleep

Just because the best current theory suggests a smallest observable time span does not mean as a consequence that time is discrete.

Re: Metric Time

#255

Post by kybernetikos »

demondemidi wrote: post #194
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.

intercalation took millennia to get right and was driven largely by starvation due to crop failure.

Which is why my system doesn't address year length. In practice I'd stick with the same leap day concept we currently use, so some years would have 36th quadday as their last day and some would have 36th pentday as their last day.

Re: Metric Time

#256

Post by throwaway569996 »

Duodecimal time units

Base unit: hour

Submultiples: dh (5 minutes), ch (25 seconds), mh (~2 seconds), ssecond (shorthand for half a mh)

Multiples: dah (12 hours), day (shorthand for 2 dah)

08:20:14 can be written as 08.411 or 08.41:2

Pros:

* Easy pseudo-metric conversions

* Easily divided by 2/3/4/6/12

* Clock is read as is, quarter past 8 is 8.3h , half past 8 is 8.6h

Cons:

* Sseconds are slightly longer than seconds (1 ss = 1.041666... s)

* No clean way to refer to minute-like units (2 ch or 3 ch?)

* Requires two more symbols (X and E)

Re: Metric Time

#257

Post by earthboundkid »

"Metric time" should mean the time it takes for light to go 10e8m, which is ~3 seconds. If that's 1 chrono, then 1 kilochrono is 55 minutes and there are around 25 kilochronos / day. 1 megachrono is 386 days. It would be a very good measurement unit for a solar system based space faring society.

Re: Metric Time

#258

Post by TheOtherHobbes »

xyzzy123 wrote: post #111
eps wrote: post #109

Earlier quoted context omitted.

No, it's not. Dividing one day into just 1000 units is way less precise unless one uses decimals, in which case it's just plain inconvenient.

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.

I take it you haven't used a microwave recently. Or done any other cooking.

Re: Metric Time

#259

Post by jermaustin1 »

kybernetikos wrote: post #244
rimliu wrote: post #204

Earlier quoted context omitted.

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.

UTC?

Re: Metric Time

#260

Post by xigoi »

nyrikki wrote: post #239
red_trumpet wrote: post #184

Earlier quoted context omitted.

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)

Base 12 being 3-smooth, any number with 2 or 3 as a factor has a reciprocal with a terminating expansion. base 60 is 5-smooth, so any number with 2,3,5 as a factor has a terminating expansion. Just as SI has to add in deg min sec for fields like astronomy. As the practical numbers are quite dense up to 60, they could divide by multiplication of the reciprocal for many more numbers. Floating point is more complicated…

Base 6 is better than base 12.

https://www.seximal.net/

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