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Metric Time

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Re: Metric Time

#311

Post by daotoad »

prometheus76 wrote: post #177
eps wrote: post #108

Earlier quoted context omitted.

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.

Now apply the same logic to measurement, and you'll see why it's so handy to use a dozenal foot for fabricating things.

Now apply that same logic to how we write our numbers. Duodecimal notation makes very clean multiplication tables and makes arithmetic easier to learn.

I'm a twelve maximalist. Let's convert SI to duodecimal prefixes. One kilometer should be 1728 meters (of course that's 1000 in duodecimal). One centimeter should be 1/144 of a meter.

I keep hoping for a chance to welcome some highly composite overlords.

Re: Metric Time

#312

Post by bloopernova »

bxparks wrote: post #262
bloopernova wrote: post #189

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.

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).

Thank you for the correction, I was going by FF not 100, whoops, sorry about that.

Re: Metric Time

#313

Post by runlevel1 »

ninju wrote: post #297
saalweachter wrote: post #226

Earlier quoted context omitted.

A second is the period of a pendulum with a length of one meter. :-) (But not really; that was originally considered as a way to standardize the meter, IIRC, but the period of a pendulum varies too much even over the area of France to be used as a concrete standard. But the relationship is remarkably close for a coincidence, like the way a rod is almost exactly five meters.)

The calculation of a second has been updated in 2019 The second is defined by taking the fixed numerical value of the cesium frequency ∆ν, the unperturbed ground-state hyperfine transition frequency of the cesium 133 atom, to be 9 192 631 770 when expressed in the unit Hz, which is equal to s−1. https://www.npl.co.uk/si-units/second

The conference where this was made official was quite a beautiful, upbeat demonstration of people from around the world coming together to agree upon a change:

https://www.youtube.com/live/qA67T7FPBME?t=498

Re: Metric Time

#314

Post by AprilArcus »

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…

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

I have some terrible news for you about statistical mechanics.

Re: Metric Time

#315

Post by reliablereason »

downvotetruth wrote: post #308
reliablereason wrote: post #298

Earlier quoted context omitted.

Which way was your comment suposed to be interpreted? Was it just a "out of context comment" on something that poped up in your mind as you read the text?

"There will be an exact point at which a certain molecule has interacted with another molecule" statement is contradictory with the uncertainty associated with time as described by quantum mechanics and molecular interactions due to Brownian motion. Material that is returned when searching for those topics will better answer your further questions about them and those above than I here.

The uncertainty principle is about unavoidable measurement "errors" (measurements that can’t be done). If you are going to measure the time (or anything) you will always get finite values. Finite values are not irrational.

Either one talks about the underlying physics or about the measurements of it. If one talks about the underlying physics all bets are of, it is unmeasurable by definition. Anything is possible bellow the measurement threshold(including irrational numbers).

If one talks about the measurements you will always get finite rational values.

Re: Metric Time

#316

Post by zeitgeistcowboy »

Lots of people are pointing out inconveniences with this decimal time system which are the same inconveniences I find with other metric systems. You can’t divide by 3, 4, 6, or 8 easily in this case.

Re: Metric Time

#317

Post by littlestymaar »

jader201 wrote: post #168
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.

Technically, yes. But measurements of weight, volume, and temperature are also part of the metric system, and those didn’t derive from the meter. Seconds are also part of the metric system, but one of the few not based on decimal/base-10. Again, I’m just speculating that the author used “metric” because it often represents decimal/base-10 measurements. Not really arguing whether they were technically correct in doing…

> But measurements of weight, volume, […] are also part of the metric system, and those didn’t derive from the meter.

For volume this is obvious nonsense since the metric system expresses volumes in … cubic meter! And even weight, a kilogram is “the weight of a liter of water” (that is a thousands of a cubic meter of water).

Re: Metric Time

#318

Post by xyzzy123 »

TheOtherHobbes wrote: post #258
xyzzy123 wrote: post #111

Earlier quoted context omitted.

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.

Yep tho most ppl use microwaves by pressing the "30s" button (I guess it would be labelled 1/2 or 1/3) n times. Other cooking seldom requires time precision watch the process and manage it by eye, rather than relying on absolute time.

Re: Metric Time

#319

Post by xattt »

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

What would the reference time segment/second represent?

Re: Metric Time

#320

Post by grishka »

btbuildem wrote: post #309
grishka wrote: post #234

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…

That to me is the key point: measures of time are so intervowen with everything else, this would be an absolute nightmare to enact without seven years of fallout and random "bugs"

Especially when you call the new units the same names as the old ones!
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