Re: Timekeeping

De: J.A. Mills <Xenolingua@...>
Fecha: Viernes 2 de Octubre de 1998 13:45


>In a message dated 10/2/98 10:20:07 AM Pacific Daylight Time,
>raybrown@CLARA.CO.UK writes:
><<
> >Nobody's satisfactorily answered my question yet.  Why doesn't a "metric"
>time
> >system even exist?  Is it because nobody can do the math?
>
> Of course they do the maths!!!!! It's not exactly high powered stuff - you
> multiply or divide by 10s or, if you stick strictly to SI system, you just
> worry about the thousands.
> Of course there just is no way the earth's daily rotation _and_ the solar
> year could both be fitted into such a system.  I guess no-one is going to
> abandon the day as a unit of time.  Ok, let's see......
> (a) Bigger units than the day.
> If we take the SI prefixes we get:
> 1000 days = 1 kiloday
> 1000 000 days = 1 megaday
> 1000 000 000 = 1 gigaday etc.
[...]
> (b) Smaller than the day.
> The day would be divided into 1000 milidays, each of which would be
divided
> into 1000 microdays, and those into 1000 nanodays etc etc.
> This is IMHO an entirely feasible system in theory.  Indeed, as I said in
> an earlier mail, the French Revolutionaries did have proposals to divide
> the day decimally.
[...]
> s it has been pointed out more than once, the second has become the
> standard SI unit of time and other SI units, e.g. the metre are defined in
> terms of the second.  A change to milidays, microdays, nanodays, would
> necessitate redifinition of otherb units and almost certainly quite costly
> readjustment and/or replacement of quite a bit of the world's scientific
> equipment.
> Ray.
>  >>
>I appreciate the lengthy response to my post, although frankly I believe
that
>your criticism of a single line at a time detracts from your argument as a
>whole.  Quite a few of your rebuttals didn't mesh with my own experience,
for
>example when you said that most of the world uses the 1997-style calendar.
>Granted they do, but in many a culture the Western calendar coexists with
>another timekeeping system.  Most of the important festivals in China are
>based on the lunar calendar.  Japan keeps records (for taxes and other
things)
>based on the current emperor.  The muslim festival of Ramadan floats around
>every year.  These things exist side by side.
>You said that the math involved wasn't terribly difficult.  Weren't you the
>one who posted the definition of a meter as being the wavelength in vacuo
of
>the orange radiation of the krypton-86 atom  (only to have to it later
>corrected as the length of the path travelled by light in vacuum during a
time
>interval of 1/299 792 458 of a second.)  Easy to comprehend, maybe, but not
>easy to come up with.
>Your argument en totale seems strikingly similar to the reasons why most
>Americans are reluctant to accept the metric system, i.e. change is bad.
And
>so I am forced to repeat:  I have no intention of "persuading the human
race"
>to do anything.  Any system of measurements has perceived advantages.  That
is
>not to preclude the creation of new systems.   I'm just asking for people
to
>help me explore the issue.
>All said, though, I _do_ like your system of nomenclature.  I imagine the
>effects on the language:  "Shoppers!  Only two more kilodays until
Christmas."

(six year till next Christmas?!!! too long)


Well, if we need SI, and if a second is defined as the time some atom
radiate a given amount of pulses, because 1/86400 of day is not a precise
measure... actually Earth's rotation period changes and, as pointed out, out
in space we wouldn't need days or years... another solution would be:

1 s (one second)
miliseconds, microseconds and nanoseconds are already used when given
response time of transistors, for example.
1 ks (one kilosecond) which is 16 minutes 40 seconds of our nomenclature.
1 Ms (megasecond) which is 11 days 13 hours 46 minutes and 40 seconds.
1 Gs (gigasecond) which is more than 31 years.

Then, in the spaceship this system is used, a day would be 100 ks, which are
some 27 hours, and 1 Ms would count as a week (or decade).  10 Ms would be a
good time for balances, but little longer than our trimestrial's.  Kids
would go to school when 200 Ms, for 30 periods fo 10 Ms each.  When they are
500 Ms old, aproppiated vocational or higher education can be followed by
the new adult (15 years 10 months of our).  A 2 Gs old person would
pensionate.

A standard working day (100 ks) would begin from kilosecond 40 to kilosecond
65.  When working in turns, each turn would be 25 ks long (almost 7 hours),
giving four turns a day.  Lights on at ks 25, of at ks 75, bars close at ks
100.

Well, I don't like this system very much.

kilodays and milidays (86,4 seconds, replaces our minute), will be an
alternative but how would we define a day for very exact physics measures.
Earth rotation period is not stable enough.  Then, we can have a scientific
calendar, based megaseconds, a civil calendar based in what ever state
decides and a religous calendar for our religion's festivities and keep
computer programs to have us informed.  We christians use already a seven
week calendar, a solilunar calendar and a solar calendar and I didn't
remember when Estern was this year nor I know when the next one will be but
it does't bother me either, if I need to know I will look at an almanac.

Unrelated question, how many of you will celebrate 31 December 1999 -> 1st
January 2000 more specially than any other year turn?

-- Carlos Th