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Metric Time

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Re: Metric Time

#231

Post by lokar »

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.

Or heating up a frozen burrito

Re: Metric Time

#232

Post by saalweachter »

sdeframond wrote: post #216
sdeframond wrote: post #171

While metric time has some appeal, I think it is not ambitious enough. Base 10 is not good. 10 just does not have enough factors, so we are left to deal with complex fractions. Let's instead use base-12 numerals and keep time unchanged! In base 12, 1 year is 10 months (or 265 days), 1 day is 20 hours, 1 hour is 50 minutes and a minute is 50 seconds. Easy enough! Edit: wait! I just realized this is still not ambitious…

So, how would we call those numbers after 10 ? "Ten", "eleven" and "twelve" can stay the same. "Thirteen" to "nineteen" are more problematic since "*teen" refers to "ten". We would like something meaning twelve-one, twelve-two and so on. Then "two-twelve" intead of "twenty" ? Feels heavy. Maybe stick to "twenty" then ? Oh, and what about retro-compatibility ? Edit: or we could go back to Imperial units. Wow Edit2: th…

If you're going to coexist with decimal, you're best off starting over with a distinct set of words.

For instance, scales have 12 notes, with seven common words for the notes (do, re, me, fa, so, la, ti). Add five more similar but distinct phonemes (go, ki, za, we, je) to insert at the position of the half notes skipped, shift la to position 1 since l looks conveniently like 1, and add nul for zero: nul, la, go, ti, do, ki, re, za, mi, fa, we, so, je.

Add in some rules for forming larger numbers (laj, goj, tij..., soj, jel, jel-la, jel-go..., jes-so, la-gross, la-gross-la, ...) and begin learning your addition tables over again (la plus la is go; go plus go is do; do plus do is mi; mi plus mi is doj).

Re: Metric Time

#233

Post by fjfaase »

I once (around 1983) met someone who had an astrological (astronomical) watch, that showed 'time' depending on the position of the earth with respect to the zodiac. He believed that periods when a sign would appear on the horizon (and another disappear) were periods that you beter could not start another activity. I am not sure if it was one made by Jaap Venker. Jaap Venker made 1500 of these watchs which now sell for hunderds of Euro/USD.

I think having a clock that depends on the position of the earth with respect to the center of our galaxy is an interesting idea.

Re: Metric Time

#234

Post by grishka »

What I don't like about this is the redefinition of the second. The length of a second and its subdivisions is so fundamental to so much of everything in our society. Other physical quantities like speed or frequency or power all depend on it. You would have to redefine everything. Kilometers per "metric hour", "metric hertz", "metric watts-hours", you get the idea.

> There is no AM or PM with metric time.

It isn't there in standard time either. It seems to be another uniquely American thing. The only time I'm exposed to AM/PM is when reading an analog clock. Or when talking to an American.

Heck, even in US, there's "military time" that is 24-hour.

Re: Metric Time

#235

Post by Synaesthesia »

Metric seconds are quite close to regular seconds since there are 100,000 metric seconds in a full day compared to 86400 regular seconds.

Which means that 40 metric seconds is about 46.3 regular seconds - I.E. something is wrong with the charts on this website.

It also means a metric minute which is 100 seconds would be 115.7 regular seconds so a bit less than two minutes, not 2.4 minutes as claimed.

Re: Metric Time

#236

Post by yakubin »

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…

The statement OP put in parentheses is a well-defined statement in mathematics. It means that the Lebesgue measure of the set of the rational numbers is zero in the space of real numbers.

Re: Metric Time

#237

Post by worthless-trash »

lesuorac wrote: post #215
xattt wrote: post #188

Earlier quoted context omitted.

> … 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.

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".

Re: Metric Time

#239

Post by nyrikki »

red_trumpet wrote: post #184
ReleaseCandidat wrote: post #158

Earlier quoted context omitted.

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)

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 than just the base as the radix also matters. C(++) finally got decimal radix support this year in the standards and IBM has had decimal floats for a long time.

FFT and encryption often use mixed radix despite being a binary base too.

It is a far more complicated subject than it appears on the surface.

But there are problems that aren't easily solvable in base 10. The degrees of a circle are an example and why navigation uses the nautical mile, where 1 nautical mile= 1 minute of latitude is an example.

12,60,360 are Superior highly composite numbers and 12 is the smallest 3-smooth and 60 is the smallest 5-smooth.

This also means that with using 360 degrees one can divide a circle or semicircle in 12 sections with just a square, 345 triangle and equalatrral triangle. Where decimal or even radians requires the square root of 2, pi, etc...

I am a fan of universal units of measurement, but had they been base 12 it would have been better IMHO. SI could be more broadly adopted if it has been base 12.

Re: Metric Time

#240

Post by worthless-trash »

eadmund wrote: post #210
taeric wrote: post #206

Earlier quoted context omitted.

Don't we have the same basic criticism going from Fahrenheit to Celsius? You go from a 10 degree swing being big to ridiculously huge. That is, arbitrary number is arbitrary, at large. Most of the "benefits" of any system won't actually be realized by most people that are using it. Consistency, on the other hand, is hugely important.

> Don't we have the same basic criticism going from Fahrenheit to Celsius? Sure, and one shouldn’t do that either. Fahrenheit’s range (0 being the freezing point of brine, almost but not quite intolerable to a human, and 100 being roughly body temperate and also almost but not quite intolerable to a human) is far more human than Celsius’s freezing-to-boiling range.

Having never used Fahrenheit in any capacity, the math for it feels inhuman.

Having grown up in metric, the values dont feel 'inhuman' just a scale that i'm familiar with. I know that my body is usually at 37, I know that water boils at 100, i know that I don't like anything below 8c or above 40c.

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