5 ms·

> but almost no one advocates for metric time People would love to but there are some nasty fractions left over if you try to impose a base 10 unit of time at

by rtkwe 6y ago

> but almost no one advocates for metric time People would love to but there are some nasty fractions left over if you try to impose a base 10 unit of time at any level above a day. Any metric time system stumbles on the fact that 1) Days do not even divide into years by 10 and there's not even a whole number of days in a year and 2) calendars should sync with the seasons to provide any real use. Also 10 days to a week is pretty long unless you include a break in the middle.

sandworm101 6y ago
>> Any metric time system stumbles on the fact that 1) Days do not even divide into years by 10 and there's not even a whole number of days in a year and 2) calendars should sync with the seasons to provide any real use. Only because a "year" is a measurement of how long it currently takes a specific planet to orbit its star. On larger scales such specifics don't matter. There is no daylight savings time in space. Metric time is a realworld thing: https://en.wikipedia.org/wiki/Metric_time https://en.wikipedia.org/wiki/Metric_time "In computing, at least internally, metric time gained widespread use for ease of computation. Unix time gives date and time as the number of seconds since January 1, 1970, and Microsoft's FILETIME as multiples of 100ns since January 1, 1601.[7] VAX/VMS uses the number of 100ns since November 17, 1858 and RISC OS the number of centiseconds since January 1, 1900."
- rtkwe 6y ago
  > Only because a "year" is a measurement of how long it currently takes a specific planet to orbit its star. On larger scales such specifics don't matter. There is no daylight savings time in space. DST is kind of meaningless here. It's not an inherent feature of the calendar and it's a dumb hack that wasn't even great when it was implemented, I'm all for getting rid of it. Sure yes when we become a multiplanet species maybe metric time will make sense for use at a human level calendar. What I was really talking about was a metric calendar system today and for use on Earth. Even off planet mapping day night to the diurnal cycle will make sense and assuming it's a planet with seasons and a breathable atmosphere the calendar will be more useful if it can match the local seasons. If that becomes an issue we'll probably have a calendar for each planet and then a universal date system used as a translation layer between different calendars and by people living in space where seasons don't screw things up. As for the variability and year that's just as bad for a metric calendar as our current Gregorian. None of that really matters though because today the calendar needs to work for people living on Earth today. If we make it to mulit-planet/solar system we can figure out Stardates then. > Metric time is a realworld thing Only at the level where humans don't really interact with it directly. No one (well I'm sure someone out there does but to a reasonable approximations no one) uses epoch time directly in their daily interactions with people. It's communication layer for machines not for people.
- gibspaulding 6y ago
  I could see dividing the day decimally working pretty well. Right now a typical work day is 1/3 of the day. This might be a good opportunity to drop it down to 3/10 of the day. Then you have the work day neatly dividing into thirds for a morning break and an afternoon lunch or vice versa. Most human level scheduling currently works at a 15 minute resolution anyways so hundredths of a day would be the perfect unit for a lot of things I'd think. Instead of meeting someone at 3:45pm, you'd just meet at today.66 or something like that.
  - WorldMaker 6y ago
    In favor of existing metric time proponents, a kilosecond is 16.7 minutes, which as you suggest is a pretty good unit of resolution for most scheduling concerns during a day of human activity. The fun problems happen because most of the prefixes between kilosecond and megasecond (nearly a fortnight at 11.6 days) and between megasecond and gigasecond (a whopping 31.7 years) are either deprecated or non-standard to begin with. For instance myriaseconds (10^4 or nearly three hours) might be useful, but myria- was dropped from the metric prefix list for good reasons.
dalbasal 6y ago
We're locked into days and years, but months, weeks, hours and minutes are arbitrary, no? Maybe we can't rationalize it all, but what's to stop us from dividing a day into 10 hours with 100 minutes each? Fuck seconds.
- lhorie 6y ago
  > what's to stop us from dividing a day into 10 hours with 100 minutes each? Same reason you can't just change the official language of your country overnight. It requires widespread consensus both in terms of users ability to use it and their systems' ability to understand it.
- rtkwe 6y ago
  We totally could [0], it feels less metric though when we're limited to messing with the time in the days and the grouping of days and still have to deal with the messy remainder of roughly 5.25 days assuming we have 'metric-y' 10 day 'weeks.' [0] Minus societal inertia and that the current calendar works well enough for all it's aesthetic messiness.
  - deleted 6y ago
    [deleted]
- WorldMaker 6y ago
  Arguably if we are sticking with the existing definitions of days and years the reason we use a base-60 is because that is a degrees system. We are respecting (approximate) circular travel. It would almost make more sense to express time in radians in that case as that is the metric measure of angle. We are about 3/4 Tau through this year, and I'm writing this at about 1.2 Pi on this day.
  - rtkwe 6y ago
    60 also has a lot of nice divisors and lays out nicely on a circle. 2, 3, 4, 5, 6, 10, 12, 15, 20, 30. If we're going to do radian measures why not just skip the extra tau and just say we're .75 through the year?
JdeBP 6y ago
People here are conflating a decimal calendar or decimal time with metric time. In its evolved form as SI, the metric system very much does have a unit of time. It is the second, and one can apply metric prefixes to it. So to those wondering what it would look like: It would look like, and does look like, kilosecond, megasecond, gigasecond, and so forth. I'm sure if you think about it you will recall having come across milliseconds, microseconds, or nanoseconds, somewhere in your lifetimes. (-:
pklausler 6y ago
Vernor Vinge's excellent novel A Deepness In The Sky, which is mostly set aboard spacecraft disconnected from planetary time cylces, uses metric measurements of time (namely Ksec and Msec), and part of the fun of reading the book was figuring out what those units meant intuitively when a character mentioned that something would take a couple Ksec to do. (It helped a bit to remember Adm. Grace Hopper's rule of thumb that "pi seconds is a nanocentury".)
- rtkwe 6y ago
  In space disconnected from any plantary cycle is probably the only setup where a metric/decimal time system makes sense because you can set the length of your 'day' to 10 kiloseconds and have it probably work out ok with humans if you change the lights to trick our circadian rhythm.
necovek 6y ago
10 days to a working week is not long if your weekends are 5 days long :) Anyway, astronomy does use "Julian Dates" which are timezone agnostic (which means era and location agnostic), rational number time markers 0-based on the "beginning of history". The problems of seasonality and divisibility remain when you start caring about human life patterns more, as you suggest.

by rtkwe 6y ago

sandworm101 6y ago

>> Any metric time system stumbles on the fact that 1) Days do not even divide into years by 10 and there's not even a whole number of days in a year and 2) calendars should sync with the seasons to provide any real use. Only because a "year" is a measurement of how long it currently takes a specific planet to orbit its star. On larger scales such specifics don't matter. There is no daylight savings time in space. Metric time is a realworld thing: https://en.wikipedia.org/wiki/Metric_time https://en.wikipedia.org/wiki/Metric_time "In computing, at least internally, metric time gained widespread use for ease of computation. Unix time gives date and time as the number of seconds since January 1, 1970, and Microsoft's FILETIME as multiples of 100ns since January 1, 1601.[7] VAX/VMS uses the number of 100ns since November 17, 1858 and RISC OS the number of centiseconds since January 1, 1900."

rtkwe 6y ago
> Only because a "year" is a measurement of how long it currently takes a specific planet to orbit its star. On larger scales such specifics don't matter. There is no daylight savings time in space. DST is kind of meaningless here. It's not an inherent feature of the calendar and it's a dumb hack that wasn't even great when it was implemented, I'm all for getting rid of it. Sure yes when we become a multiplanet species maybe metric time will make sense for use at a human level calendar. What I was really talking about was a metric calendar system today and for use on Earth. Even off planet mapping day night to the diurnal cycle will make sense and assuming it's a planet with seasons and a breathable atmosphere the calendar will be more useful if it can match the local seasons. If that becomes an issue we'll probably have a calendar for each planet and then a universal date system used as a translation layer between different calendars and by people living in space where seasons don't screw things up. As for the variability and year that's just as bad for a metric calendar as our current Gregorian. None of that really matters though because today the calendar needs to work for people living on Earth today. If we make it to mulit-planet/solar system we can figure out Stardates then. > Metric time is a realworld thing Only at the level where humans don't really interact with it directly. No one (well I'm sure someone out there does but to a reasonable approximations no one) uses epoch time directly in their daily interactions with people. It's communication layer for machines not for people.
gibspaulding 6y ago
I could see dividing the day decimally working pretty well. Right now a typical work day is 1/3 of the day. This might be a good opportunity to drop it down to 3/10 of the day. Then you have the work day neatly dividing into thirds for a morning break and an afternoon lunch or vice versa. Most human level scheduling currently works at a 15 minute resolution anyways so hundredths of a day would be the perfect unit for a lot of things I'd think. Instead of meeting someone at 3:45pm, you'd just meet at today.66 or something like that.
- WorldMaker 6y ago
  In favor of existing metric time proponents, a kilosecond is 16.7 minutes, which as you suggest is a pretty good unit of resolution for most scheduling concerns during a day of human activity. The fun problems happen because most of the prefixes between kilosecond and megasecond (nearly a fortnight at 11.6 days) and between megasecond and gigasecond (a whopping 31.7 years) are either deprecated or non-standard to begin with. For instance myriaseconds (10^4 or nearly three hours) might be useful, but myria- was dropped from the metric prefix list for good reasons.

dalbasal 6y ago

We're locked into days and years, but months, weeks, hours and minutes are arbitrary, no? Maybe we can't rationalize it all, but what's to stop us from dividing a day into 10 hours with 100 minutes each? Fuck seconds.

lhorie 6y ago
> what's to stop us from dividing a day into 10 hours with 100 minutes each? Same reason you can't just change the official language of your country overnight. It requires widespread consensus both in terms of users ability to use it and their systems' ability to understand it.
rtkwe 6y ago
We totally could [0], it feels less metric though when we're limited to messing with the time in the days and the grouping of days and still have to deal with the messy remainder of roughly 5.25 days assuming we have 'metric-y' 10 day 'weeks.' [0] Minus societal inertia and that the current calendar works well enough for all it's aesthetic messiness.
- deleted 6y ago
  [deleted]
WorldMaker 6y ago
Arguably if we are sticking with the existing definitions of days and years the reason we use a base-60 is because that is a degrees system. We are respecting (approximate) circular travel. It would almost make more sense to express time in radians in that case as that is the metric measure of angle. We are about 3/4 Tau through this year, and I'm writing this at about 1.2 Pi on this day.
- rtkwe 6y ago
  60 also has a lot of nice divisors and lays out nicely on a circle. 2, 3, 4, 5, 6, 10, 12, 15, 20, 30. If we're going to do radian measures why not just skip the extra tau and just say we're .75 through the year?

JdeBP 6y ago

People here are conflating a decimal calendar or decimal time with metric time. In its evolved form as SI, the metric system very much does have a unit of time. It is the second, and one can apply metric prefixes to it. So to those wondering what it would look like: It would look like, and does look like, kilosecond, megasecond, gigasecond, and so forth. I'm sure if you think about it you will recall having come across milliseconds, microseconds, or nanoseconds, somewhere in your lifetimes. (-:

pklausler 6y ago

Vernor Vinge's excellent novel A Deepness In The Sky, which is mostly set aboard spacecraft disconnected from planetary time cylces, uses metric measurements of time (namely Ksec and Msec), and part of the fun of reading the book was figuring out what those units meant intuitively when a character mentioned that something would take a couple Ksec to do. (It helped a bit to remember Adm. Grace Hopper's rule of thumb that "pi seconds is a nanocentury".)

rtkwe 6y ago
In space disconnected from any plantary cycle is probably the only setup where a metric/decimal time system makes sense because you can set the length of your 'day' to 10 kiloseconds and have it probably work out ok with humans if you change the lights to trick our circadian rhythm.

necovek 6y ago

10 days to a working week is not long if your weekends are 5 days long :) Anyway, astronomy does use "Julian Dates" which are timezone agnostic (which means era and location agnostic), rational number time markers 0-based on the "beginning of history". The problems of seasonality and divisibility remain when you start caring about human life patterns more, as you suggest.