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Why synchronize atomic clocks?

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  Why synchronize atomic clocks? gehan.ameresekere@gmail.com - 2017-08-28 04:36 -0700
    Re: Why synchronize atomic clocks? mlwozniak@wp.pl - 2017-08-28 05:02 -0700
      Re: Why synchronize atomic clocks? Odd Bodkin <bodkinodd@gmail.com> - 2017-08-31 16:03 +0000
        Re: Why synchronize atomic clocks? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-08-31 21:51 +0200
        Re: Why synchronize atomic clocks? mlwozniak@wp.pl - 2017-09-01 01:26 -0700
    Re: Why synchronize atomic clocks? Rafael Valls Hidalgo-Gato <rvalls162@gmail.com> - 2017-08-28 07:16 -0700
      Re: Why synchronize atomic clocks? Tom Roberts <tjroberts137@sbcglobal.net> - 2017-08-29 11:45 -0500
        Re: Why synchronize atomic clocks? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-08-30 00:54 +0200
          Re: Why synchronize atomic clocks? Prokaryotic Caspase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2017-08-29 16:31 -0700
            Re: Why synchronize atomic clocks? The Starmaker <starmaker@ix.netcom.com> - 2017-08-29 19:38 -0700
              Re: Why synchronize atomic clocks? The Starmaker <starmaker@ix.netcom.com> - 2017-08-31 14:34 -0700
                Re: Why synchronize atomic clocks? The Starmaker <starmaker@ix.netcom.com> - 2017-09-01 12:45 -0700
            Re: Why synchronize atomic clocks? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-08-30 05:47 +0200
          Re: Why synchronize atomic clocks? Tom Roberts <tjroberts137@sbcglobal.net> - 2017-08-31 13:47 -0500
            Re: Why synchronize atomic clocks? Bídníkùm Laterá <bila@wehia.ui> - 2017-08-31 20:12 +0000
            Re: Why synchronize atomic clocks? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-01 04:04 +0200
              Re: Why synchronize atomic clocks? Prokaryotic Caspase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2017-08-31 21:01 -0700
                Re: Why synchronize atomic clocks? Prokaryotic Caspase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2017-09-01 02:12 -0700
                  Re: Why synchronize atomic clocks? mlwozniak@wp.pl - 2017-09-01 04:17 -0700
              Re: Why synchronize atomic clocks? xxein1x1@gmail.com - 2017-08-31 21:34 -0700
                Re: Why synchronize atomic clocks? Tom Roberts <tjroberts137@sbcglobal.net> - 2017-09-01 11:41 -0500
            Re: Why synchronize atomic clocks? Tom Roberts <tjroberts137@sbcglobal.net> - 2017-09-01 11:17 -0500
              Re: Why synchronize atomic clocks? mlwozniak@wp.pl - 2017-09-01 09:43 -0700
              Relativity and physical reality (was: Why synchronize atomic clocks?) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-01 20:10 +0200
                Re: Relativity and physical reality (was: Why synchronize atomic clocks?) Prokaryotic Caspase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2017-09-01 12:30 -0700
                  Re: Relativity and physical reality (was: Why synchronize atomic clocks?) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-02 01:29 +0200
                    Re: Relativity and physical reality (was: Why synchronize atomic clocks?) Prokaryotic Caspase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2017-09-01 16:52 -0700
                      Re: Relativity and physical reality Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-02 02:27 +0200
                        Re: Relativity and physical reality Prokaryotic Caspase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2017-09-02 02:22 -0700
                Re: Relativity and physical reality Tom Roberts <tjroberts137@sbcglobal.net> - 2017-09-01 19:41 -0500
                  Re: Relativity and physical reality mlwozniak@wp.pl - 2017-09-02 01:01 -0700
                  Re: Relativity and physical reality Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-02 19:30 +0200
          Re: Why synchronize atomic clocks? Prokaryotic Caspase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2017-09-02 22:23 -0700
            Re: Why synchronize atomic clocks? mlwozniak@wp.pl - 2017-09-03 02:35 -0700
        Re: Why synchronize atomic clocks? kenseto <setoken@att.net> - 2017-08-30 07:28 -0700
        Re: Why synchronize atomic clocks? Rafael Valls Hidalgo-Gato <rvalls162@gmail.com> - 2017-08-30 09:47 -0700
          Re: Why synchronize atomic clocks? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-08-31 00:03 +0200
            Re: Why synchronize atomic clocks? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-08-31 00:22 +0200
          Re: Why synchronize atomic clocks? Tom Roberts <tjroberts137@sbcglobal.net> - 2017-08-30 17:58 -0500
            Re: Why synchronize atomic clocks? Rafael Valls Hidalgo-Gato <rvalls162@gmail.com> - 2017-08-31 13:56 -0700
              Re: Why synchronize atomic clocks? gehan.ameresekere@gmail.com - 2017-08-31 23:17 -0700
                Re: Why synchronize atomic clocks? Rafael Valls Hidalgo-Gato <rvalls162@gmail.com> - 2017-09-01 08:45 -0700
              Re: Why synchronize atomic clocks? Tom Roberts <tjroberts137@sbcglobal.net> - 2017-09-01 11:54 -0500
                Re: Why synchronize atomic clocks? Gary Harnagel <hitlong@yahoo.com> - 2017-09-01 12:39 -0700
                  Re: Why synchronize atomic clocks? Prokaryotic Caspase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2017-09-01 12:51 -0700
                Re: Why synchronize atomic clocks? gehan.ameresekere@gmail.com - 2017-09-04 19:26 -0700
                  Re: Why synchronize atomic clocks? Tom Roberts <tjroberts137@sbcglobal.net> - 2017-09-05 11:06 -0500
                    Re: Why synchronize atomic clocks? gehan.ameresekere@gmail.com - 2017-09-05 22:53 -0700
                      Re: Why synchronize atomic clocks? Paparios <mrios@ing.puc.cl> - 2017-09-06 05:25 -0700
                        Re: Why synchronize atomic clocks? mlwozniak@wp.pl - 2017-09-06 05:40 -0700
                      Re: Why synchronize atomic clocks? Tom Roberts <tjroberts137@sbcglobal.net> - 2017-09-06 17:22 -0500
        Re: Why synchronize atomic clocks? mlwozniak@wp.pl - 2017-09-01 01:24 -0700
        Re: Why synchronize atomic clocks? kenseto <setoken@att.net> - 2017-09-06 06:42 -0700
          Re: Why synchronize atomic clocks? mlwozniak@wp.pl - 2017-09-06 07:04 -0700
    Re: Why synchronize atomic clocks? "Dono," <sa_ge@comcast.net> - 2017-08-28 07:49 -0700
    Re: Why synchronize atomic clocks? Ed Lake <detect@newsguy.com> - 2017-08-28 08:12 -0700
      Re: Why synchronize atomic clocks? Ed Lake <detect@newsguy.com> - 2017-08-28 09:11 -0700
        Re: Why synchronize atomic clocks? Odd Bodkin <bodkinodd@gmail.com> - 2017-08-28 11:15 -0500
        Re: Why synchronize atomic clocks? Ed Lake <detect@newsguy.com> - 2017-08-28 09:44 -0700
          Re: Why synchronize atomic clocks? Odd Bodkin <bodkinodd@gmail.com> - 2017-08-28 11:52 -0500
      Re: Why synchronize atomic clocks? gehan.ameresekere@gmail.com - 2017-08-28 23:59 -0700
        Re: Why synchronize atomic clocks? Ed Lake <detect@newsguy.com> - 2017-09-01 14:01 -0700
          Re: Why synchronize atomic clocks? Dirk Van de moortel <dirkvandemoortel@hotspam.not> - 2017-09-02 00:20 +0200
            Re: Why synchronize atomic clocks? Dirk Van de moortel <dirkvandemoortel@hotspam.not> - 2017-09-02 00:21 +0200
    Re: Why synchronize atomic clocks? Sylvia Else <sylvia@not.at.this.address> - 2017-08-29 17:11 +1000
    Re: Why synchronize atomic clocks? Tom Roberts <tjroberts137@sbcglobal.net> - 2017-08-29 18:38 -0500
      Re: Why synchronize atomic clocks? gehan.ameresekere@gmail.com - 2017-08-31 23:38 -0700
        Re: Why synchronize atomic clocks? Tom Roberts <tjroberts137@sbcglobal.net> - 2017-09-01 20:09 -0500

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#430232 — Why synchronize atomic clocks?

The Atomic clock has done away with the need to synchronize clocks, it would seem because atomic clocks run at the same rate. Presumably, Einstein's' theory of relativity pre-dates the atomic clock, and even time zones. 

If two clocks are moved apart at a rate so slowly that relativistic effects can be neglected, there is no need to synchronize them.

http://galileoandeinstein.physics.virginia.edu/lectures/synchronizing.html

Or are we referring to synchronizing moving clocks (relative to our local frame?) But that is an impossibly complicated task.

https://en.wikipedia.org/wiki/Einstein_synchronisation

"Einstein synchronisation (or Poincaré–Einstein synchronisation) is a convention for synchronising clocks at different places by means of signal exchanges. This synchronisation method was used already by telegraphers in the middle 19th century, but was popularized by Henri Poincaré and Albert Einstein who applied it to light signals and recognized its fundamental role in relativity theory. Its principal value is for clocks within a single inertial frame"

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#430236

Because sane people want clocks to be synchronized.

Only insane crazies believing common sense is a set
of prejudices can want them to unsynchronize
(and, as we can check at GPS, even they only want
it theoretically).

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#430561

<mlwozniak@wp.pl> wrote:
> Because sane people want clocks to be synchronized.

No, you do. But you're not sane. 

> 
> Only insane crazies believing common sense is a set
> of prejudices can want them to unsynchronize
> (and, as we can check at GPS, even they only want
> it theoretically).
> 



-- 
Odd Bodkin -- maker of fine toys, tools, tables

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#430589

Odd Bodkin wrote:

> <mlwozniak@wp.pl> wrote:
>> Because sane people want clocks to be synchronized.
> 
> No, you do.

Add me :)

> But you're not sane.

Probably true, but non sequitur.

-- 
PointedEars

Twitter: @PointedEars2
Please do not cc me. / Bitte keine Kopien per E-Mail.

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#430642

W dniu czwartek, 31 sierpnia 2017 18:04:00 UTC+2 użytkownik Odd Bodkin napisał:
> <mlwozniak@wp.pl> wrote:
> > Because sane people want clocks to be synchronized.
> 
> No, you do. But you're not sane. 

I'm not, but sane people do too.
Check at GPS, poor idiot.

> > Only insane crazies believing common sense is a set
> > of prejudices can want them to unsynchronize
> > (and, as we can check at GPS, even they only want
> > it theoretically).

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#430249

El lunes, 28 de agosto de 2017, 7:36:03 (UTC-4), gehan.am...@gmail.com  escribió:
> The Atomic clock has done away with the need to synchronize clocks, it would seem because atomic clocks run at the same rate. Presumably, Einstein's' theory of relativity pre-dates the atomic clock, and even time zones. 
>
ANY measuring device is submitted to the same physical laws, and under different
physical conditions (velocity, gravitational potential, temperature, etc.), ANY 
two measuring devices MUST be adjusted to measure both the same desired physical 
magnitude, being time NOT at all an exception.

GPS atomic clocks are affected by velocity (-7 microsec./day) and gravitational
potential (+45 microsec./day) changes, an EXPERIMENTAL FACT since the first 1977
GPS satellite launching, a HUGE support for the original 1905 Einstein Relativity (denoted 1905R), including its two postulates.

RVHG (Rafael Valls Hidalgo-Gato)

.....................

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#430387

On 8/28/17 9:16 AM, Rafael Valls Hidalgo-Gato wrote:
> GPS atomic clocks are affected by velocity (-7 microsec./day) and gravitational
> potential (+45 microsec./day) changes, an EXPERIMENTAL FACT 

That is NOT any sort of fact at all, experimental or otherwise; IT IS WRONG.

It is NOT the clocks that are affected, it is the RECEPTION OF SIGNALS from the 
clocks that are affected.

	The on-board Cs133 oscillator ticks at 9,192,631,770 Hz -- that's
	what these words mean. This oscillator IS NOT affected by its
	velocity (relative to anything else) or its gravitational potential
	(relative to anything else), because IT DEFINES WHAT "1 SECOND"
	MEANS IN THE SATELLITE.

Note that the SIGNALS emitted by the satellite and received on the geoid are 
affected by both its velocity relative to the ECI and its gravitational 
potential relative to the geoid. In GPS satellite clocks, the divider between 
the Cs133 oscillator and the clock mechanism has been modified so the Doppler 
shift of the SIGNALS from satellite to a receiver at rest on the geoid is 
canceled by the modification.

	That effect on SIGNALS is clear and undeniable. If the clocks were
	affected as you claim, the GPS system would not work. And both
	Special and General Relativity would be refuted. So we KNOW that
	the clocks are not affected.

Tom Roberts

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#430405

Tom Roberts wrote:

> On 8/28/17 9:16 AM, Rafael Valls Hidalgo-Gato wrote:
>> GPS atomic clocks are affected by velocity (-7 microsec./day) and
>> gravitational potential (+45 microsec./day) changes, an EXPERIMENTAL FACT
> 
> That is NOT any sort of fact at all, experimental or otherwise; IT IS
> WRONG.
> 
> It is NOT the clocks that are affected, it is the RECEPTION OF SIGNALS
> from the clocks that are affected.
> 
> The on-board Cs133 oscillator ticks at 9,192,631,770 Hz -- that's
> what these words mean. This oscillator IS NOT affected by its
> velocity (relative to anything else) or its gravitational potential
> (relative to anything else), because IT DEFINES WHAT "1 SECOND"
> MEANS IN THE SATELLITE.

ISTM that you are merely performing high-level nitpicking here.  From the 
perspective of an observer who is stationary (or almost stationary by 
comparison) in the ECI frame, the atomic clocks aboard GPS satellites *are* 
affected by their motion relative to the observer (and in a different way by 
their greater distance from Earth’s center of mass).

The principle of relativity states that there is *no* preferred frame of 
reference.  That means that physical reality does not exist only in the rest 
frame: Where observers in different frames disagree about an observation of 
the same object, and the difference in the quantities in their statements 
corresponds to the Lorentz transformation of those quantities, *all* of them 
are correct.  Yet that the rest frame would be the preferred frame against 
which the truth of all statements must be measured is exactly the argument 
that you are using here and have been using before.
 
> Note that the SIGNALS emitted by the satellite and received on the geoid
> are affected by both its velocity relative to the ECI and its
> gravitational potential relative to the geoid. In GPS satellite clocks,
> the divider between the Cs133 oscillator and the clock mechanism has been
> modified so the Doppler shift of the SIGNALS from satellite to a receiver
> at rest on the geoid is canceled by the modification.

AFAIK the clocks have been modified *before* being sent into orbit so that 
_the gravitational time dilation on the ground_ is being canceled instead: 
The clocks have been modified to "tick" slower than normal on the ground, so 
that they would "tick" in orbit as fast as the ground clocks if there were 
no time dilation due to relative motion.

Because by contrast to the height of the satellite orbits, the Doppler shift 
of the signal would depend on the relative velocity between satellite and 
receiver which cannot be known in advance.  In fact, I think that the 
(relativistic) Doppler shift of the GPS signal is completely irrelevant for 
the proper operation of the GPS, and GNSSs in general.

See also: <http://www.astronomy.ohio-state.edu/~pogge/Ast162/Unit5/gps.html>
 
-- 
PointedEars

Twitter: @PointedEars2
Please do not cc me. / Bitte keine Kopien per E-Mail.

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#430409

On Tuesday, August 29, 2017 at 5:54:28 PM UTC-5, Thomas 'PointedEars' Lahn wrote:
> Tom Roberts wrote:

> > The on-board Cs133 oscillator ticks at 9,192,631,770 Hz -- that's
> > what these words mean. This oscillator IS NOT affected by its
> > velocity (relative to anything else) or its gravitational potential
> > (relative to anything else), because IT DEFINES WHAT "1 SECOND"
> > MEANS IN THE SATELLITE.
> 
> ISTM that you are merely performing high-level nitpicking here.  From the 
> perspective of an observer who is stationary (or almost stationary by 
> comparison) in the ECI frame, the atomic clocks aboard GPS satellites *are* 
> affected by their motion relative to the observer (and in a different way by 
> their greater distance from Earth’s center of mass).

The issue is far more than just "high-level nitpicking". 

It lies at the heart of popular misunderstandings of the meaning of relativity.

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#430429

Prokaryotic Caspase Homolog wrote:
> 
> On Tuesday, August 29, 2017 at 5:54:28 PM UTC-5, Thomas 'PointedEars' Lahn wrote:
> > Tom Roberts wrote:
> 
> > > The on-board Cs133 oscillator ticks at 9,192,631,770 Hz -- that's
> > > what these words mean. This oscillator IS NOT affected by its
> > > velocity (relative to anything else) or its gravitational potential
> > > (relative to anything else), because IT DEFINES WHAT "1 SECOND"
> > > MEANS IN THE SATELLITE.
> >
> > ISTM that you are merely performing high-level nitpicking here.  From the
> > perspective of an observer who is stationary (or almost stationary by
> > comparison) in the ECI frame, the atomic clocks aboard GPS satellites *are*
> > affected by their motion relative to the observer (and in a different way by
> > their greater distance from Earth’s center of mass).
> 
> The issue is far more than just "high-level nitpicking".
> 
> It lies at the heart of popular misunderstandings of the meaning of relativity.



How can you measure time with clocks made by man when Time is not made
by man?

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#430604

The Starmaker wrote:
> 
> Prokaryotic Caspase Homolog wrote:
> >
> > On Tuesday, August 29, 2017 at 5:54:28 PM UTC-5, Thomas 'PointedEars' Lahn wrote:
> > > Tom Roberts wrote:
> >
> > > > The on-board Cs133 oscillator ticks at 9,192,631,770 Hz -- that's
> > > > what these words mean. This oscillator IS NOT affected by its
> > > > velocity (relative to anything else) or its gravitational potential
> > > > (relative to anything else), because IT DEFINES WHAT "1 SECOND"
> > > > MEANS IN THE SATELLITE.
> > >
> > > ISTM that you are merely performing high-level nitpicking here.  From the
> > > perspective of an observer who is stationary (or almost stationary by
> > > comparison) in the ECI frame, the atomic clocks aboard GPS satellites *are*
> > > affected by their motion relative to the observer (and in a different way by
> > > their greater distance from Earth’s center of mass).
> >
> > The issue is far more than just "high-level nitpicking".
> >
> > It lies at the heart of popular misunderstandings of the meaning of relativity.
> 
> How can you measure time with clocks made by man when Time is not made
> by man?



Now if Time itself wanted to measure the twins, it would only use one clock.

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#430717

The Starmaker wrote:
> 
> The Starmaker wrote:
> >
> > Prokaryotic Caspase Homolog wrote:
> > >
> > > On Tuesday, August 29, 2017 at 5:54:28 PM UTC-5, Thomas 'PointedEars' Lahn wrote:
> > > > Tom Roberts wrote:
> > >
> > > > > The on-board Cs133 oscillator ticks at 9,192,631,770 Hz -- that's
> > > > > what these words mean. This oscillator IS NOT affected by its
> > > > > velocity (relative to anything else) or its gravitational potential
> > > > > (relative to anything else), because IT DEFINES WHAT "1 SECOND"
> > > > > MEANS IN THE SATELLITE.
> > > >
> > > > ISTM that you are merely performing high-level nitpicking here.  From the
> > > > perspective of an observer who is stationary (or almost stationary by
> > > > comparison) in the ECI frame, the atomic clocks aboard GPS satellites *are*
> > > > affected by their motion relative to the observer (and in a different way by
> > > > their greater distance from Earth’s center of mass).
> > >
> > > The issue is far more than just "high-level nitpicking".
> > >
> > > It lies at the heart of popular misunderstandings of the meaning of relativity.
> >
> > How can you measure time with clocks made by man when Time is not made
> > by man?
> 
> Now if Time itself wanted to measure the twins, it would only use one clock.


If you tell Time
"i notice a difference in time sitting on a girls lap and sitting on a stove."

Time will tell you..."You must be imagining things, I checked my clock, there was no difference in Time."


Relativity has nothing to do with Time.


You people simply don't understand...Time.

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#430433

Prokaryotic Caspase Homolog wrote:

> On Tuesday, August 29, 2017 at 5:54:28 PM UTC-5, Thomas 'PointedEars' Lahn
> wrote:
>> Tom Roberts wrote:
>> > The on-board Cs133 oscillator ticks at 9,192,631,770 Hz -- that's
>> > what these words mean. This oscillator IS NOT affected by its
>> > velocity (relative to anything else) or its gravitational potential
>> > (relative to anything else), because IT DEFINES WHAT "1 SECOND"
>> > MEANS IN THE SATELLITE.
>> ISTM that you are merely performing high-level nitpicking here.  From the
>> perspective of an observer who is stationary (or almost stationary by
>> comparison) in the ECI frame, the atomic clocks aboard GPS satellites
>> *are* affected by their motion relative to the observer (and in a
>> different way by their greater distance from Earth’s center of mass).
> 
> The issue is far more than just "high-level nitpicking".
> 
> It lies at the heart of popular misunderstandings of the meaning of
> relativity.

Yes, probably I was too lenient with Tom in that paragraph.  However, my 
next paragraph, not quoted (nor read?) by you, should have made my meaning 
clear.

-- 
PointedEars

Twitter: @PointedEars2
Please do not cc me. / Bitte keine Kopien per E-Mail.

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#430571

On 8/29/17 8/29/17   5:54 PM, Thomas 'PointedEars' Lahn wrote:
> Tom Roberts wrote:
>> On 8/28/17 9:16 AM, Rafael Valls Hidalgo-Gato wrote:
>>> GPS atomic clocks are affected by velocity (-7 microsec./day) and
>>> gravitational potential (+45 microsec./day) changes, an EXPERIMENTAL FACT
>> That is NOT any sort of fact at all, experimental or otherwise; IT IS
>> WRONG.
> 
> ISTM that you are merely performing high-level nitpicking here. 

No. Not at all. This is a common misconception among students in general, and 
all too many people around here. I repeat: clocks are NOT affected, by ether 
their motion (relative to anything) or their gravitational potential (relative 
to anywhere). But the reception of signals from the clocks can be affected.

Note that if the clocks were affected, then SR simply could not be valid -- the 
PoR could not be valid, as the laws of physics that govern the clock's ticking 
would not be the same in all (locally) inertial frames.

> From the
> perspective of an observer who is stationary (or almost stationary by
> comparison) in the ECI frame, the atomic clocks aboard GPS satellites *are*
> affected by their motion relative to the observer (and in a different way by
> their greater distance from Earth’s center of mass).

No, they aren't. By claiming the clocks are affected you have denied the 
validity of SR.

You have made the same error and ASSUMED that the SIGNALS from the satellite 
clock are not affected by the satellite's motion or the earth's gravity. Both of 
those implicit assumptions are WRONG. Moreover, once one accounts for those 
effects on the signals, there is no "room" for the clocks to be affected.

Make no mistake: the Principle of Relativity applies, and the (local) laws of 
physics are the same in any (locally) inertial frame. So the laws of Cs133 
hyperfine emission are the same in the satellite as on earth's geoid, and that 
atom oscillates at 9,192,631,770 Hz in both places (and anywhere else).

The GPS specifications are both clear and explicit: the divider between the 
Cs133 oscillator and the on-board chip clock is modified so the chip clock is 
10.22999999543 MHz. One can calculate the effect ON THE SIGNALS of the 
transmission from satellite to a receiver on the ground, and the result is that 
on the geoid the chip clock is received at 10.23000000000 MHz [#].

That could not happen if the clock was affected.

     [#] On average, or after correcting for the directional variation
     of the Doppler shift.

> [.. long mish-mash, some of which is right, but the conclusions are wrong]
Note the satellite's chip clock is 10.22999999543 MHz. Period. This is true 
before launch when the satellite is on the ground, and it is true in orbit. 
Because measuring such a clock must ALWAYS be done using a co-located and 
co-moving instrument. If you measure SIGNALS from the clock then of course you 
must account for any effects on those signals, BUT YOU DON'T.

Tom Roberts

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#430595

Tom Roberts wrote:

> On 8/29/17 8/29/17   5:54 PM, Thomas 'PointedEars' Lahn wrote:
>> Tom Roberts wrote:
>>> On 8/28/17 9:16 AM, Rafael Valls Hidalgo-Gato wrote:
>>>> GPS atomic clocks are affected by velocity (-7 microsec./day) and
>>>> gravitational potential (+45 microsec./day) changes, an EXPERIMENTAL
>>>> FACT
>>> That is NOT any sort of fact at all, experimental or otherwise; IT IS
>>> WRONG.
>> 
>> ISTM that you are merely performing high-level nitpicking here.
> 
> No. Not at all. This is a common misconception among students in
> general, and all too many people around here. I repeat: clocks are NOT
> affected, by ether their motion (relative to anything) or their
> gravitational potential (relative to anywhere). But the reception of
> signals from the clocks can be affected.

He is not an any students, but just stupid. Never been inside a 
laboratory, as the rest of us. He doesn't even know what a measurement is. 
He is an idiot.

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#430619

Tom Roberts wrote:

> On 8/29/17 8/29/17   5:54 PM, Thomas 'PointedEars' Lahn wrote:
>> From the perspective of an observer who is stationary (or almost
>> stationary by comparison) in the ECI frame, the atomic clocks aboard GPS
>> satellites *are* affected by their motion relative to the observer (and
>> in a different way by their greater distance from Earth’s center of
>> mass).
> 
> No, they aren't. By claiming the clocks are affected you have denied the
> validity of SR.

No, I have affirmed it, in particular I have affirmed the principle of 
relativity: There is no preferred frame of reference.

*You* have denied it by saying that every measurement of an object must be 
made in the rest frame of that object in order to be considered real.
 
>> [.. long mish-mash, some of which is right, but the conclusions are
>> [wrong]
> Note the satellite's chip clock is 10.22999999543 MHz. […]

A clock is not a frequency.  Perhaps if you elaborated on what you meant, a 
truth value could be assigned, but the statement as it is, is just nonsense.

-- 
PointedEars

Twitter: @PointedEars2
Please do not cc me. / Bitte keine Kopien per E-Mail.

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#430623

On Thursday, August 31, 2017 at 9:04:18 PM UTC-5, Thomas 'PointedEars' Lahn wrote:
> Tom Roberts wrote:
> 
> > On 8/29/17 8/29/17   5:54 PM, Thomas 'PointedEars' Lahn wrote:
> >> From the perspective of an observer who is stationary (or almost
> >> stationary by comparison) in the ECI frame, the atomic clocks aboard GPS
> >> satellites *are* affected by their motion relative to the observer (and
> >> in a different way by their greater distance from Earth’s center of
> >> mass).
> > 
> > No, they aren't. By claiming the clocks are affected you have denied the
> > validity of SR.
> 
> No, I have affirmed it, in particular I have affirmed the principle of 
> relativity: There is no preferred frame of reference.

Your use of the word "affected" is significantly different from the manner 
in which I would use the word. As Tom might state, we are dealing with a 
*pun* in regards to your usage of the word "affect". We see the same word, 
and entirely different thoughts run through our heads.

To illustrate, let us consider a different phenomenon: length contraction.

If we observe length contraction in a rod passing by us at high speed, is 
the rod "affected" by its motion relative to us?

To Lorentz and his followers, who believed in a dynamical interpretation of
length contraction, the answer would be "yes". They believed in actual material
effects on the rod that could be measured by an observer co-moving with the
rod. If the rod were conductive, the co-moving observer could measure changes
in resistance. If the rod were transparent, the co-moving observer could measure
birefringence due to strain on the material of the rod. And so on and so forth.
https://en.wikipedia.org/wiki/Trouton%E2%80%93Rankine_experiment
https://en.wikipedia.org/wiki/Experiments_of_Rayleigh_and_Brace

    I am referring to Lorentz *before* Poincare wrote his well-known series 
    of mails to Lorentz where Poincare corrected him on various minor math 
    errors and demonstrated the group nature of his transforms.  

If I am asked whether an atomic clock is "affected" by its motion relative to
me, my understanding of the word "affected" is that the questioner is asking
whether physical changes to the clock are responsible for its difference
in measured ticking rate. In other words, can rate changes in the clock's
ticking be a result of compressive distortions experienced by the clock as a
result of its motions relative to me?

Your use of the word "affect" would lead you to agree that the length of a
rod is "affected" by its motions relative to us, while at the same time you 
would vehemently deny that the rod is "affected" by its passage through the
aether in the manner that Lorentz visualized. 

Your use of the word "affected" is confusing and in conflict with my personal
understanding of the word.

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#430645

On Thursday, August 31, 2017 at 11:01:35 PM UTC-5, Prokaryotic Caspase Homolog wrote:

> If we observe length contraction in a rod passing by us at high speed, is 
> the rod "affected" by its motion relative to us?
> 
> To Lorentz and his followers, who believed in a dynamical interpretation of
> length contraction, the answer would be "yes". They believed in actual material
> effects on the rod that could be measured by an observer co-moving with the
> rod. If the rod were conductive, the co-moving observer could measure changes
> in resistance. If the rod were transparent, the co-moving observer could measure
> birefringence due to strain on the material of the rod. And so on and so forth.
> https://en.wikipedia.org/wiki/Trouton%E2%80%93Rankine_experiment
> https://en.wikipedia.org/wiki/Experiments_of_Rayleigh_and_Brace
> 
>     I am referring to Lorentz *before* Poincare wrote his well-known series 
>     of mails to Lorentz where Poincare corrected him on various minor math 
>     errors and demonstrated the group nature of his transforms.  

By pointing out to Lorentz his math error, Poincare was able to demonstrate 
the non-detectability of the aether. Strangely enough, Poincare continued to
believe in the dynamical interpretation of the Lorentz transforms and the
existence of the aether to the end of his life. 

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#430654

W dniu piątek, 1 września 2017 11:12:25 UTC+2 użytkownik Prokaryotic Caspase Homolog napisał:

> By pointing out to Lorentz his math error, Poincare was able to demonstrate 
> the non-detectability of the aether. Strangely enough, Poincare continued to
> believe in the dynamical interpretation of the Lorentz transforms and the
> existence of the aether to the end of his life.

What an obvious antisemitist.

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#430624

On Thursday, August 31, 2017 at 10:04:18 PM UTC-4, Thomas 'PointedEars' Lahn wrote:
> Tom Roberts wrote:
> 
> > On 8/29/17 8/29/17   5:54 PM, Thomas 'PointedEars' Lahn wrote:
> >> From the perspective of an observer who is stationary (or almost
> >> stationary by comparison) in the ECI frame, the atomic clocks aboard GPS
> >> satellites *are* affected by their motion relative to the observer (and
> >> in a different way by their greater distance from Earth’s center of
> >> mass).
> > 
> > No, they aren't. By claiming the clocks are affected you have denied the
> > validity of SR.
> 
> No, I have affirmed it, in particular I have affirmed the principle of 
> relativity: There is no preferred frame of reference.
> 
> *You* have denied it by saying that every measurement of an object must be 
> made in the rest frame of that object in order to be considered real.
>  
> >> [.. long mish-mash, some of which is right, but the conclusions are
> >> [wrong]
> > Note the satellite's chip clock is 10.22999999543 MHz. […]
> 
> A clock is not a frequency.  Perhaps if you elaborated on what you meant, a 
> truth value could be assigned, but the statement as it is, is just nonsense.
> 
> -- 
> PointedEars
> 
> Twitter: @PointedEars2
> Please do not cc me. / Bitte keine Kopien per E-Mail.

xxein:  Thanks Pointy.  Your use of the calculations is exactly the same as mine.  I keep forgetting to mention that if an unadjusted orbiting clock and the ground clock reunite afterward (synchronized before launch of course), they would show an elapsed time difference that has nothing to do with signal transmission.  Also traveling twins in case they were forgotten.  I guess using authorative language does not necessarily make one a genuine authority.

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