The unit of time in the metric system is the second. Whenever the rate of anything is measured in metric units, it’s so many somethings (meters, litres, kilograms, etc.) per second.
For times shorter than a second, we’re already using metric: milliseconds, microseconds, nanoseconds, etc. I’ve seen some measurements using kiloseconds and once megaseconds. (Note that this concept is turned into the standard time-measuring system for a spacefaring culture in Vernor Vinge’s science-fiction novel A Deepness in the Sky.
I read some books by Vernor Vinge (his Zones of Thought books) where the time units were kiloseconds, megaseconds, etc. They didn’t use days, weeks, years, etc. This is science fiction where Earth as we know it is long gone and forgotten.
At least I think it was those books…maybe someone will back me up as I don’t have them on me ATM.
It seemed to work ok in the books, and I guess it would work for us as well, it’s just that it would be a hassle to switch.
It seems like a bit of a copout to use the “regular” second for metric measurements, though. It’s an arbitrary length of time that isn’t related to any other metric unit, whereas the meter is derived from the circumference of the Earth, and the units for area, volume, and mass are based on the meter. The metric second should be something like the period of a 1-meter pendulum, or the length of time it takes for a dropped object to fall 1 meter.
The thing is, whether it should have been changed around or not, the second is now one of the fundamental units of the metric system. It’s one of the seven basic units of the entire system, and if you redefine it now, you’d have to redefine pretty much the entire system. (Note that even one of the other basic units is now defined in terms of the second.)
Metric time was proposed back when the metric system was introduced. Scientific American ran an article about it a few decades ago, complete with engravings of Metric Clocks produced ro measure metric time. For some reason, it never caught on, even in France.
The problem with time, and the reason it resisted decimalization, is that nature saddled us with two incompatible standard units–the day and the year.
The day measures the cycle of daytime and dark, and the year measures the cycle of the seasons. We can’t live without either one. Long periods of time are going to be measured in years, and shorter periods in days. If I told you something was going to happen a kiloday from now, your first thought would be, “What time of year will that be?”
No doubt, we could decimalize the intermediate units. There’s no reason why hours, minutes, and seconds couldn’t be decimal fractions of a day. But even if you do that, you’re stuck with the year for longer time scales–unlike the situation with respect to distance, where atomic to astronomical distances can all be measured in meters.
Another factor is that the day and year are universal, so there was less local variation in Eighteenth Century time measures than in distance measures–and less pressure for a new standard unit.
So for distance and mass, you could collapse a series of non-standard local measures into a new universal measure on one standard scale. For time, you’d be collapsing what was already a relatively universal measure into a new measure on two standard scales (the day and the year). The benefits of the latter were, and are, less compelling.
Of course, in an ideal world we’d all switch to base 30 (2 X 3 X 5). The additional prime factor would provide us more arithmetical tricks to ease multiplication and division. 30 hour days might be a drag though.
That’s the model I went with. I referred to them as “millidays” rather than “metric minutes”, and “centimils” (hundredths of thousandths of a day) rather than “metric seconds”, but same diff.
Why not dispense with the colon? If we’re going decimal-time here, now is 317.18094 (based on a start of day equivalent to 6 AM in conventional time, i.e., millidays since average sunrise).
I had the conversion charts all worked out (in both directions) and could convert in my head for awhile before my obsessive-compulsive brain switched to a different focus. Need I mention that me coming up with the same idea in no way rules out your being crazy, and might even indicate the opposite?
Good point. And one year is close to 360 times as long as one day. This must have been irresistible to the Babylonians who used a 60-based numbe system. What is more natural than to divide time up in units of 60 and do that six times with 5 extra days of celebration of how clever we are.