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Relativity and physical reality (was: Why synchronize atomic clocks?)

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Tom Roberts wrote:

> On 8/31/17 2:49 PM, 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 confirmed it, in particular I have confirmed the principle of
>> relativity.  There is no preferred frame of reference.
>> *You* have denied it by saying that any measurement must be made in the
>> rest frame in order to be real.
> 
> [I never said anything about "real" -- YOU need to learn how
> to read without putting in your own additions, which are
> nearly always wrong. "Real" HAS NOTHING TO DO WITH THIS.]

Oh, but it has.  By definition, reality is *what one observes*.
 
> Apparently you do not know how English applies here.

To say that something is “affected” means that something about it is 
different compared to another situation (that might be called “normal”), 
yes?

<https://en.oxforddictionaries.com/definition/affected>

> When one says "that clock is affected and ticks slowly", one is talking
> about THE CLOCK AND NOTHING ELSE.

We can only know about the state of the clock because *we observe the clock* 
(in some way).  Who is to say which observer is correct about the current 
state of the clock?

Answer: Nobody.  Because from the PoR follows that *there is no preferred 
reference frame*.  There is _not_ only *one* reference frame, nor even only 
a specific number of reference frames, in which the only correct 
statement(s) about the *same* thing can be made.

AISB, from special relativity already follows that statements from all 
observers about the *same* object are correct as long as they are correct 
for one observer and correspond to the Lorentz transformation of the 
quantities used in the statements of the observers about the *same* object.

For example, let us assume that the two of us are identical twins, and that 
I state that I observe a light source that emits predominantly red light.  I 
point you to that light source.  But you disagree with me, claiming that you 
see the same light source to be emitting predominantly ultraviolet light.

How could that be?  How can the *same* light source be described so 
differently by two such people?

Because you are in a futuristic spaceship moving towards the light source at 
a high relative speed, and I am _not_.  For you, the relativistic Doppler 
effect lets the emitted light appear blue-shifted; but not for me, as I am, 
say, at rest to the same light source (to illustrate, let that be a red 
giant star).

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

Now, who is to say which one of the two of us is correct about the color of 
the light – or more physically speaking, about its frequency and wavelength?  
*Nobody*.  Even though our statements *differ*, we are *both* correct about 
the color/frequency of the light, *from our respective perspective*.

See also:

<http://channel.nationalgeographic.com/genius/videos/time-is-not-absolute/>

> So this inherently means that you must measure THE CLOCK AND NOTHING ELSE,
> which means for a GPS satellite clock you must be in the satellite -- you
> CANNOT use signals from the clock to measure JUST THE CLOCK.

Yes I (one) can.  I just depends on the kind of the emitted signals.
 
> Apparently you do not know what the PoR actually is.
> 
> The PoR states that the LAWS OF PHYSICS are the same in every (locally)
> inertial frame. In particular, it does NOT make any claim that
> measurements are the same in all inertial frames.

Straw man.
 
> […] 
> I do not understand why this is so hard for you (and others around here).
> It OUGHT to be obvious that SIGNALS from a satellite don't necessarily
> reflect what happens to their clocks,

Straw man, again.

You fail to appreciate the fact that “what happens to a clock” or “that/how 
a clock is affected” *depends on who observes that clock*.

I do not subscribe to your interpretation that (because of the use of the 
term “proper” in the theories of relativity as qualifier for the quantities 
measured in that situation) the only correct statement about an object is 
the one that is made by an observer at rest in that object’s rest frame.

If that is a problem for you, then we will have to agree to disagree, 
because I am convinced that Einstein would agree with me:

,-<https://www.britannica.com/topic/Albert-Einstein-on-Space-Time-1987141>
| 
| All our thoughts and concepts are called up by sense-experiences and have 
| a meaning only in reference to these sense-experiences.  […]

> [tl;dr]

-- 
PointedEars

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

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Thread

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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