Re: "A diagram of C23 basic types"

From	Michael S <already5chosen@yahoo.com>
Newsgroups	comp.lang.c
Subject	Re: "A diagram of C23 basic types"
Date	2025-04-19 23:15 +0300
Organization	A noiseless patient Spider
Message-ID	<20250419231546.00006a20@yahoo.com> (permalink)
References	(20 earlier) <87tt6p11bw.fsf@nosuchdomain.example.com> <vtmv30$tfkg$1@dont-email.me> <vtr8bd$vfa6$1@dont-email.me> <vtvkdk$vh8f$1@dont-email.me> <vu0b64$1jhpi$1@dont-email.me>

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On Sat, 19 Apr 2025 17:15:42 +0200
David Brown <david.brown@hesbynett.no> wrote:

> On 19/04/2025 09:46, Janis Papanagnou wrote:
> > On 17.04.2025 17:56, David Brown wrote:  
> >> On 16/04/2025 02:53, James Kuyper wrote:  
> >>> On 4/15/25 18:56, Keith Thompson wrote:
> >>> ...  
> >>>> The uncertainty in the timing of January 1, 1970, where 1970 is a
> >>>> year number in the current almost universally accepted Gregorian
> >>>> calendar, is essentially zero.  
> >>>
> >>> Modern Cesium clock are accurate to about 1 ns/day.That's an
> >>> effect large enough that we can measure it, but cannot correct
> >>> for it. We know that the clocks disagree with each other, but the
> >>> closest we can do to correcting for that instability is to
> >>> average over 450 different clock; the average is 10 times more
> >>> stable than the individual clocks.
> >>>
> >>> Note: the precision of cesium clocks has improved log-linearly
> >>> since the 1950s. They're 6 orders of magnitude better in 2008
> >>> than they were in 1950. Who knows how much longer that will
> >>> continue to be true? 
> >>
> >> I don't think cesium is still the current standard for the highest
> >> precision atomic clocks.  
> > 
> > Well, the "Cesium _fountain_" atomic clocks are still amongst
> > the most precise and they are in use in the world wide net of
> > atomic clocks that are interconnected to measure TAI.[*]  And
> > the standard second is _defined_ on Caesium based transitions.
> >   
> 
> Caesium fountain clocks are old school, but still used.  Rubidium is 
> popular because it is cheaper, and very high stability atomic clocks
> use aluminium or strontium.  Caesium is still the basis for the
> current definition of the second, but that will change in the next
> decade or so as accuracy of timekeeping has moved well beyond the
> original caesium standard.
> 
> >> But anyway, the newest breakthrough is thorium
> >> nuclear clocks, which IIRC are 5 orders of magnitude more stable
> >> than cesium clocks.  (And probably 5 orders of magnitude more
> >> expensive...)  
> > 
> > I've not heard of Thorium based clocks. But I've heard of
> > "optical clocks" that are developed to get more precise and
> > more stable versions of atomic clock times.
> >   
> 
> It was only last year that a good measurement of the resonant 
> frequencies of the Thorium 229 nucleus was achieved - the science bit
> is done, now the engineering bit needs to be finished to get a
> practical nuclear clock.
> 
> 


Record my prediction: it's not going to happen.

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Re: "A diagram of C23 basic types" Lawrence D'Oliveiro <ldo@nz.invalid> - 2025-04-14 04:33 +0000
  Re: "A diagram of C23 basic types" candycanearter07 <candycanearter07@candycanearter07.nomail.afraid> - 2025-04-14 17:40 +0000
    Re: "A diagram of C23 basic types" Kaz Kylheku <643-408-1753@kylheku.com> - 2025-04-14 17:46 +0000
      Re: "A diagram of C23 basic types" Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2025-04-15 09:41 +0200
    Re: "A diagram of C23 basic types" BGB <cr88192@gmail.com> - 2025-04-14 13:36 -0500
      Re: "A diagram of C23 basic types" Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-04-14 15:15 -0700
      Re: "A diagram of C23 basic types" Lawrence D'Oliveiro <ldo@nz.invalid> - 2025-04-14 22:33 +0000
        Re: "A diagram of C23 basic types" Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-04-14 15:56 -0700
          Re: "A diagram of C23 basic types" Lawrence D'Oliveiro <ldo@nz.invalid> - 2025-04-14 23:41 +0000
            Re: "A diagram of C23 basic types" Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-04-14 17:57 -0700
            Re: "A diagram of C23 basic types" James Kuyper <jameskuyper@alumni.caltech.edu> - 2025-04-14 23:25 -0400
              Re: "A diagram of C23 basic types" Lawrence D'Oliveiro <ldo@nz.invalid> - 2025-04-15 04:11 +0000
                Re: "A diagram of C23 basic types" James Kuyper <jameskuyper@alumni.caltech.edu> - 2025-04-15 10:06 -0400
                Re: "A diagram of C23 basic types" Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-04-15 15:56 -0700
                Re: "A diagram of C23 basic types" "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2025-04-15 17:04 -0700
                Re: "A diagram of C23 basic types" James Kuyper <jameskuyper@alumni.caltech.edu> - 2025-04-15 20:53 -0400
                Re: "A diagram of C23 basic types" David Brown <david.brown@hesbynett.no> - 2025-04-17 17:56 +0200
                Re: "A diagram of C23 basic types" Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2025-04-19 09:46 +0200
                Re: "A diagram of C23 basic types" David Brown <david.brown@hesbynett.no> - 2025-04-19 17:15 +0200
                Re: "A diagram of C23 basic types" Michael S <already5chosen@yahoo.com> - 2025-04-19 23:15 +0300
                Re: "A diagram of C23 basic types" David Brown <david.brown@hesbynett.no> - 2025-04-21 20:34 +0200
                Re: "A diagram of C23 basic types" Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-04-21 14:28 -0700
                Re: "A diagram of C23 basic types" Michael S <already5chosen@yahoo.com> - 2025-04-22 01:07 +0300
                Re: "A diagram of C23 basic types" candycanearter07 <candycanearter07@candycanearter07.nomail.afraid> - 2025-04-22 19:30 +0000
                Re: "A diagram of C23 basic types" Tim Rentsch <tr.17687@z991.linuxsc.com> - 2025-05-05 16:40 -0700
                Re: "A diagram of C23 basic types" Michael S <already5chosen@yahoo.com> - 2025-04-22 00:28 +0300
                Re: "A diagram of C23 basic types" Lawrence D'Oliveiro <ldo@nz.invalid> - 2025-04-15 22:58 +0000
                Re: "A diagram of C23 basic types" James Kuyper <jameskuyper@alumni.caltech.edu> - 2025-04-15 21:02 -0400
                Re: "A diagram of C23 basic types" Lawrence D'Oliveiro <ldo@nz.invalid> - 2025-04-16 07:42 +0000
              Re: "A diagram of C23 basic types" BGB <cr88192@gmail.com> - 2025-04-15 00:00 -0500
                Re: "A diagram of C23 basic types" scott@slp53.sl.home (Scott Lurndal) - 2025-04-15 14:08 +0000
                Re: "A diagram of C23 basic types" BGB <cr88192@gmail.com> - 2025-04-15 12:29 -0500
                Re: "A diagram of C23 basic types" James Kuyper <jameskuyper@alumni.caltech.edu> - 2025-04-15 18:57 -0400
                Re: "A diagram of C23 basic types" Lawrence D'Oliveiro <ldo@nz.invalid> - 2025-04-15 23:01 +0000
                Re: "A diagram of C23 basic types" Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-04-15 17:10 -0700
                Re: "A diagram of C23 basic types" Kaz Kylheku <643-408-1753@kylheku.com> - 2025-04-16 02:11 +0000
                Re: "A diagram of C23 basic types" Lawrence D'Oliveiro <ldo@nz.invalid> - 2025-04-15 23:00 +0000
          Re: "A diagram of C23 basic types" "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2025-04-14 18:46 -0700
            Re: "A diagram of C23 basic types" Lawrence D'Oliveiro <ldo@nz.invalid> - 2025-04-15 04:14 +0000
            Re: "A diagram of C23 basic types" James Kuyper <jameskuyper@alumni.caltech.edu> - 2025-04-15 10:19 -0400
              Re: "A diagram of C23 basic types" Kaz Kylheku <643-408-1753@kylheku.com> - 2025-04-15 14:28 +0000
              Re: "A diagram of C23 basic types" "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2025-04-15 12:17 -0700
                Re: "A diagram of C23 basic types" "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2025-04-15 16:20 -0700
                Re: "A diagram of C23 basic types" Lawrence D'Oliveiro <ldo@nz.invalid> - 2025-04-17 03:03 +0000
                Re: "A diagram of C23 basic types" "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2025-04-16 22:34 -0700
                Re: "A diagram of C23 basic types" "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2025-04-16 22:38 -0700
              Re: "A diagram of C23 basic types" Lawrence D'Oliveiro <ldo@nz.invalid> - 2025-04-15 23:10 +0000
        Re: "A diagram of C23 basic types" BGB <cr88192@gmail.com> - 2025-04-14 19:43 -0500
          Re: "A diagram of C23 basic types" Lawrence D'Oliveiro <ldo@nz.invalid> - 2025-04-15 04:15 +0000
            Re: "A diagram of C23 basic types" BGB <cr88192@gmail.com> - 2025-04-15 00:40 -0500
              Re: "A diagram of C23 basic types" David Brown <david.brown@hesbynett.no> - 2025-04-15 19:22 +0200
                Re: "A diagram of C23 basic types" BGB <cr88192@gmail.com> - 2025-04-15 12:54 -0500
                Re: "A diagram of C23 basic types" scott@slp53.sl.home (Scott Lurndal) - 2025-04-15 19:10 +0000
                Re: "A diagram of C23 basic types" BGB <cr88192@gmail.com> - 2025-04-15 19:54 -0500
                Re: "A diagram of C23 basic types" David Brown <david.brown@hesbynett.no> - 2025-04-18 20:03 +0200
              Re: "A diagram of C23 basic types" Lawrence D'Oliveiro <ldo@nz.invalid> - 2025-04-15 22:56 +0000
                Re: "A diagram of C23 basic types" BGB <cr88192@gmail.com> - 2025-04-15 23:48 -0500
                Re: "A diagram of C23 basic types" Lawrence D'Oliveiro <ldo@nz.invalid> - 2025-04-16 07:41 +0000
                Re: "A diagram of C23 basic types" David Brown <david.brown@hesbynett.no> - 2025-04-18 20:10 +0200
          Re: "A diagram of C23 basic types" scott@slp53.sl.home (Scott Lurndal) - 2025-04-15 14:10 +0000
            Re: "A diagram of C23 basic types" BGB <cr88192@gmail.com> - 2025-04-15 13:00 -0500
              Re: "A diagram of C23 basic types" Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-04-15 16:42 -0700
                Re: "A diagram of C23 basic types" candycanearter07 <candycanearter07@candycanearter07.nomail.afraid> - 2025-04-16 14:00 +0000
                Re: "A diagram of C23 basic types" Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-04-16 12:48 -0700
                Re: "A diagram of C23 basic types" scott@slp53.sl.home (Scott Lurndal) - 2025-04-16 20:04 +0000
                Re: "A diagram of C23 basic types" BGB <cr88192@gmail.com> - 2025-04-16 16:10 -0500
                Re: "A diagram of C23 basic types" Richard Heathfield <rjh@cpax.org.uk> - 2025-04-16 23:13 +0100
                Re: "A diagram of C23 basic types" Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-04-16 16:31 -0700
                Re: "A diagram of C23 basic types" Richard Heathfield <rjh@cpax.org.uk> - 2025-04-17 01:05 +0100
                Re: "A diagram of C23 basic types" Kaz Kylheku <643-408-1753@kylheku.com> - 2025-04-17 01:26 +0000
                Re: "A diagram of C23 basic types" Lawrence D'Oliveiro <ldo@nz.invalid> - 2025-04-17 23:18 +0000
                Re: "A diagram of C23 basic types" Richard Heathfield <rjh@cpax.org.uk> - 2025-04-28 07:52 +0100
                Re: "A diagram of C23 basic types" Lawrence D'Oliveiro <ldo@nz.invalid> - 2025-04-30 23:57 +0000
                Re: "A diagram of C23 basic types" Richard Heathfield <rjh@cpax.org.uk> - 2025-05-01 06:17 +0100
                Re: "A diagram of C23 basic types" Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-04-16 16:11 -0700
                Re: "A diagram of C23 basic types" Lawrence D'Oliveiro <ldo@nz.invalid> - 2025-04-17 23:16 +0000
                Re: "A diagram of C23 basic types" Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2025-04-29 02:10 +0200
                Re: "A diagram of C23 basic types" Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-04-28 19:20 -0700
                Re: "A diagram of C23 basic types" Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2025-04-29 08:37 +0200
                Re: "A diagram of C23 basic types" scott@slp53.sl.home (Scott Lurndal) - 2025-04-29 13:14 +0000
                Re: "A diagram of C23 basic types" James Kuyper <jameskuyper@alumni.caltech.edu> - 2025-04-28 23:34 -0400
                Re: "A diagram of C23 basic types" Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2025-04-29 08:44 +0200
                Re: "A diagram of C23 basic types" Lawrence D'Oliveiro <ldo@nz.invalid> - 2025-04-30 23:58 +0000
                Re: "A diagram of C23 basic types" Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-04-30 17:15 -0700
                Re: "A diagram of C23 basic types" candycanearter07 <candycanearter07@candycanearter07.nomail.afraid> - 2025-04-29 05:10 +0000
                Re: "A diagram of C23 basic types" James Kuyper <jameskuyper@alumni.caltech.edu> - 2025-04-29 01:24 -0400
                Re: "A diagram of C23 basic types" BGB <cr88192@gmail.com> - 2025-04-29 13:02 -0500
                Re: "A diagram of C23 basic types" Richard Heathfield <rjh@cpax.org.uk> - 2025-04-29 19:25 +0100
                Re: "A diagram of C23 basic types" scott@slp53.sl.home (Scott Lurndal) - 2025-04-29 19:00 +0000

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