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Re: Why synchronize atomic clocks?

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Rafael Valls Hidalgo-Gato wrote:

> El martes, 29 de agosto de 2017, 12:45:49 (UTC-4), tjrob137  escribió:
>> 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.
> 
> You are rejecting a historical fact, the launching of the first GPS
> satellite from ground to the carefully designed operative orbit on the
> same 1905R stationary system introduced by Einstein at the end of Section
> 4 of his Jun30 paper, a 1686 Newtonian mechanics center of mass one (an
> entity introduced on Corollary IV) corresponding to all the Earth's parts
> interacting according to his THREE Axioms or Laws of Motion, today denoted
> ECI, what occurs on July 1977.

That is just pseudo-scientific word salad.

> [more word salad]
> The GPS designed 10.23 MHz standard frequency determining the same ECI
> time in every stationary space point, is NEVER a SIGNAL transmitted or
> received.

Such a nonsense, it is not even wrong.

<https://en.wikipedia.org/wiki/Global_Positioning_System>

> It is already present on all synchronized operative GPS clocks
> with that frequency,

What a nonsense.  A signal is not present in a clock, and certainly the GPS 
signal is not present in any atomic clock of any GPS satellite.

The GPS signal, other than it carries the time *information* in the 
*payload* (*data*) from the satellite to the receiver, and once per day the 
GPS time information from the GPS ground clocks to the satellites to 
synchronize the satellites’ clocks with GPS time (which is necessary because 
of the satellites’ motion relative to the ground), has nothing to do with 
the atomic clock of any GPS satellite.

> including the satellite and ground ones. It is the relative time to the
> stationary ECI system that 1905 Einstein defines on Section 1.

Cite evidence.  Quote the sentence or paragraph in

<http://einsteinpapers.press.princeton.edu/vol2-trans/155>

where you think that Einstein defines the ECI _frame_.

    [Don’t bother.  You have no clue what you are talking about.  Einstein 
    had no idea about the ECI frame or the GPS, especially not in (his) 1905
    (paper).  Those are more modern concepts and technologies.  In
    particular, GNSSs do not work without the application of the concepts
    of *general* relativity (*from 1915*/1916) – a well-confirmed theory,
    but *at odds with Newton’s law of universal gravitation*, in particular
    regarding the relativity of time *dependent on the differences between
    gravitational potentials/spacetime curvatures*.]
 
>> 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.
> 
> You are completely confused.

No, at least in that regard *you* are.  The oscillator in its rest frame is 
not affected by the velocity of that frame relative to the ground receiver 
or its gravitational potential.

What is affected is the *difference* in *elapsed time* as measured by the 
ground clocks and the satellite clocks, respectively.  It is never zero.

> The Cs133 oscillator NOT affected by velocity or gravitational potential
> that you refer does NOT exist at all.

Yes, it does.

<https://en.wikipedia.org/wiki/Atomic_clock#Mechanism>

> We know that precisely by the NEW experimental evidence obtained since the
> first GPS satellite launching.

What a nonsense.  It is common knowledge that GPS satellites have atomic 
clocks based on Cs-133 on board.  They do because atomic clocks are the most 
precise clocks that humankind has produced to date.

> It is not the first time that I explain to you this in all detail,
> including dates, institutions and official documents.

If so, why are repeating this nonsense?
 
>> 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.
>
> I will repeat once more. [snip]

Thanks; but no, thanks.

>> 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.
>> 
> That effect on CLOCKS is clear and undeniable. If the SIGNALS from the
> transmitters were affected as you claim, the GPS system would not work.
> And both 1905R and General Relativity would be refuted. But it is an
> EXPERIMENTAL FACT that GPS system WORKS VERY GOOD. So we KNOW that the
> SIGNALS are not affected, traveling always on the ECI stationary space at
> the same uniform isotropic velocity c

That much is true.

> and constant telecommunication link carrier frequencies, totally 
> independent on satellite and receptor

(_receiver_)

Since the relativistic Doppler effect is an experimental fact, your 
statement is wrong.  In fact, the frequency of the receivable signal differs 
from that of the transmitted signal due to relative speed, but the relative 
speeds are much less than the speed of light, so the differences are very 
small.

The relation between the frequency at the source (satellite) f_S and the 
received/observed frequency f_o is

  f_o = γ (1 − v∕c) f_S                      Relativistic Doppler effect,

where

    γ = 1∕√(1 − v²∕c²),

and v is the relative speed between sender and receiver (negative if sender 
and receiver are moving towards each other), or IOW the sender’s relative 
speed as measured in the receiver’s rest frame or vice-versa.

<https://en.wikipedia.org/wiki/Relativistic_Doppler_effect>

The maximum possible relative speed v_m for an observer at rest on the 
surface of Terra (Earth) is measured when a GPS satellite is moving against 
Terra’s rotation.  The average rotation speed of Terra is

   v_r = u_T/T_T

where u_T is the circumference of Terra and T_T is Terra’s rotation period 
(the time it takes the planet to rotate by 360°).  We find:

   v_r ≈ (40'000 km)∕(1 d) ≈ (40'000 km)∕(86'400 s) ≈ 463 m/s

(compare the infobox in <https://en.wikipedia.org/wiki/Earth>).

We also know that each GPS satellite completes an approximately circular 
orbit at a height of h ≈ 20'000 km above the terrestrial surface in T_S ≈ 
12 h (standard hours; 1 h = 3'600 s).  We find the orbital speed of a GPS 
satellite to be

   v_S = u_S∕T_S

where u_S is the circumference of the satellite’s orbit, and

   u_S = 2 π (h + r_T)

   v_S ≈ 2 π (h + r_T)∕(43'200 s)

where r_T ≈ 6371 km is the radius of Terra.  Then

   v_S ≈ 4 km/s.

v_m then is, *precisely*, the *relativistic* composition of the speeds v_r 
and v_S (according to the Lorentz transformation, _not_ the Galilean 
transformation):

     v_m = (v_r + v_S)∕(1 + v_r v_S∕c²) ≈ 4.463 km/s

(obviously, as the speeds are much lower than the speed of light, the result 
here is virtually indistinguishable from that of the Galilean addition of 
speeds).

<https://en.wikipedia.org/wiki/Velocity-addition_formula#Special_relativity>

Setting v := v_m we arrive at

       γ = 1∕√(1 − v²∕c²) ≈ 1.00000000000000011082

where with c = 299'792.458 km∕s it means that

   f_o = γ (1 − v/c) f_S
       ≈ 1.00000000000000011082 (1 − 0.000014886966) f_S
   f_o ≈ 0.99998511 f_S.

Now, granted, that is not much of a difference, but it is _not_ *no* 
difference (the coefficient would be 1), and for the L1 GPS signal at 
1575.42 MHz it makes a difference of ca. 0.0235 MHz or 23.5 kHz between 
transmitted and received signal.

This is also only the most optimistic form of the worst case scenario if one 
considers that the receiver is usually moving relative to the surface as 
well.  For example, a jet airplane can reach ground speeds of ca. 0.5 km∕s 
(Mach 1.5) or more.

However, this does not have anything to do with the general operation of
the GPS or GNSSs in general.  Receivers for GNSS signals are obviously 
designed to handle a range of frequencies (that range must be the greater
the expected ground speeds of the receiver), and the calculation of the 
geoposition using the GPS method does _not_ involve the frequency of the 
GNSS signal *at all*.  (See the article referred above.)

> velocities, in total agreement with the three original 1686NM Axioms and
> two 1905R Postulates, with Euclidean geometry, Cartesian coordinates,
> Newtonian equations, and space separated from time.

More pseudoscience.  Evidently, due to the Doppler effect, neither in 
Newtonian nor in relativistic mechanics is the received frequency 
independent of the motion of the sender relative to the receiver.

Also, the remarkable precision with which the predictions of special and 
general relativity (both on which the GPS depends), and their application in 
other theories, continue to be confirmed, and those of Newtonian mechanics 
are essentially _falsified_, leaves no doubt for a *reasonable* person that 
space can _not_ be considered separate from time.

<https://en.wikipedia.org/wiki/Tests_of_special_relativity>
<https://en.wikipedia.org/wiki/Tests_of_general_relativity>

-- 
PointedEars

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

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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
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      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
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        Re: Why synchronize atomic clocks? Tom Roberts <tjroberts137@sbcglobal.net> - 2017-08-31 13:47 -0500
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              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
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                Re: Relativity and physical reality (was: Why synchronize atomic clocks?) Prokaryotic Caspase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2017-09-01 16:52 -0700
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          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
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              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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