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Re: Do you like gedanken?

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=?iso-8859-2?Q?Maciej_Wo=BCniak?= <mlwozniak@wp.pl> writes:

>|Atomic clocks are better clocks than the rotating earth is.

>Better for supporting The Shit of insane guru, no doubt.
>Worse for about everything else. Including GPS, that keeps
>rotating Earth time.

Actually GPS operates on TAI time, using the atomic clock
second that is slightly different than the Earth rotation
second. It has to - it is that sensitive to the small
changes that a "1 second = 1/86400 of an earth rotation
period" definition would have.  We see this from the need
to adjust for the tiny GR time difference.

GPS satellites also keep track of the difference between
TAI time and UT1 (currently 36 seconds) and broadcasts it.
GPS receivers wanting the clock time get the TAI time and
add that offset to it.

>And those leap seconds - why are your atomic clocks
>adjusted?

They aren't; that's because they are more accurate than
the Earth itself.  They are so accurate that there is a
problem that 1 second is no longer 1/86400 of an earth
rotation, so once in a while a leap second is added.
Otherwise rotational midnight starts happening at 12:00:01
AM, after a couple years at 12:00:02 AM, then 12:00:03 AM
etc.  Now once that is done there are two times, TAI time
which never has a leap second and UT1 which now differs by
36 seconds because of accumulated leap seconds.  If your
time needs are such that you need to keep as close as possible
to how the sun is located, which is what 99.9% of people on
earth think of as time, use UT1 and add a leap second once in
a while.  If you are doing precision scientific stuff which
requires an exact measurement of the time between Event A
and Event B, you cannot deal with the occasional minute with
61 seconds, so better use TAI time.

> For a very simple reason: we need to keep
>our time compatibile with Earth cycle more than we
>need them to keep the atomic cycle.

Depends on the use.  99.9% of people need to keep synched
with the earth's cycles, better add the leap seconds and
use UT1.  Fancy scientific stuff has to use TAI time as
the earth is not accurate enough, and leap seconds would do
bad things.

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Do you like gedanken? mlwozniak@wp.pl - 2016-07-17 23:41 -0700
  Re: Do you like gedanken? PD <TheDraperFamily@gmail.com> - 2016-07-18 08:12 -0700
    Re: Do you like gedanken? Maciej Woźniak <mlwozniak@wp.pl> - 2016-07-18 18:03 +0200
      Re: Do you like gedanken? PD <TheDraperFamily@gmail.com> - 2016-07-18 09:19 -0700
        Re: Do you like gedanken? Odd Bodkin <bodkinodd@gmail.com> - 2016-07-18 11:34 -0500
          Re: Do you like gedanken? mlwozniak@wp.pl - 2016-07-18 23:27 -0700
            Re: Do you like gedanken? JanPB <filmart@gmail.com> - 2016-07-19 10:54 -0700
              Re: Do you like gedanken? Odd Bodkin <bodkinodd@gmail.com> - 2016-07-19 13:08 -0500
              Re: Do you like gedanken? Maciej Woźniak <mlwozniak@wp.pl> - 2016-07-19 21:47 +0200
                Re: Do you like gedanken? JanPB <filmart@gmail.com> - 2016-07-19 14:32 -0700
                Re: Do you like gedanken? mlwozniak@wp.pl - 2016-07-19 23:04 -0700
                Re: Do you like gedanken? JanPB <filmart@gmail.com> - 2016-07-19 23:19 -0700
                Re: Do you like gedanken? mlwozniak@wp.pl - 2016-07-20 00:00 -0700
        Re: Do you like gedanken? Maciej Woźniak <mlwozniak@wp.pl> - 2016-07-18 19:27 +0200
          Re: Do you like gedanken? PD <TheDraperFamily@gmail.com> - 2016-07-18 13:09 -0700
            Re: Do you like gedanken? Maciej Woźniak <mlwozniak@wp.pl> - 2016-07-18 22:16 +0200
        Re: Do you like gedanken? mlwozniak@wp.pl - 2016-07-19 00:07 -0700
          Re: Do you like gedanken? mlwozniak@wp.pl - 2016-07-19 01:52 -0700
            Re: Do you like gedanken? moroney@world.std.spaamtrap.com (Michael Moroney) - 2016-07-19 14:20 +0000
              Re: Do you like gedanken? Maciej Woźniak <mlwozniak@wp.pl> - 2016-07-19 17:38 +0200
              Re: Do you like gedanken? Maciej Woźniak <mlwozniak@wp.pl> - 2016-07-19 17:50 +0200
                Re: Do you like gedanken? moroney@world.std.spaamtrap.com (Michael Moroney) - 2016-07-19 16:50 +0000
                Re: Do you like gedanken? JanPB <filmart@gmail.com> - 2016-07-19 10:55 -0700
                Re: Do you like gedanken? Maciej Woźniak <mlwozniak@wp.pl> - 2016-07-19 21:45 +0200
                Re: Do you like gedanken? moroney@world.std.spaamtrap.com (Michael Moroney) - 2016-07-20 17:49 +0000
                Re: Do you like gedanken? Maciej Woźniak <mlwozniak@wp.pl> - 2016-07-20 21:48 +0200
                Re: Do you like gedanken? moroney@world.std.spaamtrap.com (Michael Moroney) - 2016-07-20 20:49 +0000
                Re: Do you like gedanken? Maciej Woźniak <mlwozniak@wp.pl> - 2016-07-21 00:16 +0200
                Re: Do you like gedanken? JanPB <filmart@gmail.com> - 2016-07-20 16:17 -0700
                Re: Do you like gedanken? mlwozniak@wp.pl - 2016-07-20 23:12 -0700
                Re: Do you like gedanken? JanPB <filmart@gmail.com> - 2016-07-20 23:46 -0700
                Re: Do you like gedanken? mlwozniak@wp.pl - 2016-07-20 23:54 -0700
                Re: Do you like gedanken? JanPB <filmart@gmail.com> - 2016-07-21 11:16 -0700
                Re: Do you like gedanken? Maciej Woźniak <mlwozniak@wp.pl> - 2016-07-21 22:44 +0200
                Re: Do you like gedanken? JanPB <filmart@gmail.com> - 2016-07-21 16:19 -0700
                Re: Do you like gedanken? mlwozniak@wp.pl - 2016-07-21 23:28 -0700
                Re: Do you like gedanken? moroney@world.std.spaamtrap.com (Michael Moroney) - 2016-07-21 15:08 +0000
                Re: Do you like gedanken? Maciej Woźniak <mlwozniak@wp.pl> - 2016-07-21 18:08 +0200
                Re: Do you like gedanken? JanPB <filmart@gmail.com> - 2016-07-21 11:18 -0700
                Re: Do you like gedanken? Maciej Woźniak <mlwozniak@wp.pl> - 2016-07-21 22:46 +0200
                Re: Do you like gedanken? JanPB <filmart@gmail.com> - 2016-07-21 16:18 -0700
                Re: Do you like gedanken? mlwozniak@wp.pl - 2016-07-21 23:24 -0700
                Re: Do you like gedanken? JanPB <filmart@gmail.com> - 2016-07-22 00:22 -0700
                Re: Do you like gedanken? mlwozniak@wp.pl - 2016-07-22 00:35 -0700
                Re: Do you like gedanken? mlwozniak@wp.pl - 2016-07-21 00:04 -0700
  Re: Do you like gedanken? JanPB <filmart@gmail.com> - 2016-07-18 13:23 -0700
    Re: Do you like gedanken? Maciej Woźniak <mlwozniak@wp.pl> - 2016-07-18 23:43 +0200
      Re: Do you like gedanken? JanPB <filmart@gmail.com> - 2016-07-18 15:22 -0700
        Re: Do you like gedanken? mlwozniak@wp.pl - 2016-07-18 23:24 -0700

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