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Re: Valid and Invalid Arguments in Special Relativity

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On Thursday, 22 June 2017 15:17:29 UTC+2, Gary Harnagel  wrote:

> Not really.  If you claim without evidence that the laws of physics are
> different from what they are locally, you are violating the law of
> parsimony (Occam's razor).  It amounts to sheer speculation.

Sorry, I'am not claiming anything.
I'am only asking the question if the speed of light is constant.
What you are saying (my interpretation): Yes locally.
My reply would be: that is not a full answer.
IMO a better answer would be: it depends.
 
> 
> For your approach, you at least need a distance tool, else you can't set
> up a distance d0.  And you need an assumption that d0 doesn't chance when
> you move it.  And you need TWO synchronized clocks since you can't directly
> compare time of flight at different locations and you're only measuring
> one way.  
This text is in agreement with my understanding that to measure the speed
of light, in order to answer my question is difficult.
> It's much easier to measure round-trip time since you only need
> one clock.  
In that case you get an average speed. 
> But you still need a distance tool.
Ofcourse.

> > > But in fact, it is much more convenient to measure the round-trip time and
> > > multiply the ratio by 2.
> > 
> > In that view you calculate the average speed. The physical process that 
> > describes how photons move can be more subtle. 
> 
> Without evidence it is sheer speculation.  

That is correct, but you "close the book" by calling the speed of light
a physical constant (locally), stopping all possible future experiments. 

> > > > and secondly is there eveywhere in the universe a vacuum.
> > > 
> > > We're not all over the universe, so that's irrelevant.
> > 
> > As far as I know we don't live in a vacuum, so for us it is relevant.
> 
> Only locally.  Saying we don't live in a vacuum is obvious, but most of
> space is pretty empty.

This is also a reason to assume that the speed of light is not every where
the same.
 
> > And is this in agreement with the concept of the:
> >     "invariance of the speed of light"? 
> > I have my doubts.
> 
> The invariance of the speed of light is local.  If you were in a g field
> and measured the speed of light over a distance short enough so the g
> field didn't significantly vary, you would measure it as c.  The Shapiro
> effect occurs when the light passes through a changing g field.

This implies that when the g field varies significant you can measure
the it as not being equal to c (to c0).
It also means that when you measure it more accurately in a g field 
that varies from place to place, you can measure different values for c.
(Even here on earth). This complies with my answer: it depends

Nicolaas Vroom

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Valid and Invalid Arguments in Special Relativity Pentcho Valev <pvalev@yahoo.com> - 2017-06-19 03:57 -0700
  Re: Valid and Invalid Arguments in Special Relativity Rhett Doucet <ttdh@etoe.ee> - 2017-06-19 13:30 +0000
  Re: Valid and Invalid Arguments in Special Relativity Gary Harnagel <hitlong@yahoo.com> - 2017-06-19 06:35 -0700
  Re: Valid and Invalid Arguments in Special Relativity Pentcho Valev <pvalev@yahoo.com> - 2017-06-19 07:47 -0700
    Re: Valid and Invalid Arguments in Special Relativity Gary Harnagel <hitlong@yahoo.com> - 2017-06-19 09:19 -0700
  Re: Valid and Invalid Arguments in Special Relativity Tom Roberts <tjroberts137@sbcglobal.net> - 2017-06-19 22:51 -0500
    Re: Valid and Invalid Arguments in Special Relativity Ned Latham <nedlatham@woden.valhalla.oz> - 2017-06-20 02:36 -0500
      Re: Valid and Invalid Arguments in Special Relativity Gary Harnagel <hitlong@yahoo.com> - 2017-06-20 04:06 -0700
        Re: Valid and Invalid Arguments in Special Relativity Ned Latham <nedlatham@woden.valhalla.oz> - 2017-06-20 06:51 -0500
          Re: Valid and Invalid Arguments in Special Relativity Odd Bodkin <bodkinodd@gmail.com> - 2017-06-20 08:26 -0500
            Re: Valid and Invalid Arguments in Special Relativity Ned Latham <nedlatham@woden.valhalla.oz> - 2017-06-20 09:09 -0500
              Re: Valid and Invalid Arguments in Special Relativity Odd Bodkin <bodkinodd@gmail.com> - 2017-06-21 11:12 -0500
              Re: Valid and Invalid Arguments in Special Relativity Odd Bodkin <bodkinodd@gmail.com> - 2017-06-21 16:56 +0000
          Re: Valid and Invalid Arguments in Special Relativity Gary Harnagel <hitlong@yahoo.com> - 2017-06-20 07:07 -0700
            Re: Valid and Invalid Arguments in Special Relativity Ned Latham <nedlatham@woden.valhalla.oz> - 2017-06-20 10:38 -0500
              Re: Valid and Invalid Arguments in Special Relativity Gary Harnagel <hitlong@yahoo.com> - 2017-06-20 09:53 -0700
                Re: Valid and Invalid Arguments in Special Relativity Ned Latham <nedlatham@woden.valhalla.oz> - 2017-06-20 19:50 -0500
                Re: Valid and Invalid Arguments in Special Relativity Gary Harnagel <hitlong@yahoo.com> - 2017-06-20 19:45 -0700
                Re: Valid and Invalid Arguments in Special Relativity Lipek Mniak <iluka@sskwpiw.pp> - 2017-06-21 12:18 +0000
              Re: Valid and Invalid Arguments in Special Relativity Odd Bodkin <bodkinodd@gmail.com> - 2017-06-21 11:12 -0500
            Re: Valid and Invalid Arguments in Special Relativity Nicolaas Vroom <nicolaas.vroom@pandora.be> - 2017-06-21 13:22 -0700
              Re: Valid and Invalid Arguments in Special Relativity Gary Harnagel <hitlong@yahoo.com> - 2017-06-21 18:08 -0700
                Re: Valid and Invalid Arguments in Special Relativity Nicolaas Vroom <nicolaas.vroom@pandora.be> - 2017-06-22 02:10 -0700
                Re: Valid and Invalid Arguments in Special Relativity mlwozniak@wp.pl - 2017-06-22 02:52 -0700
                Re: Valid and Invalid Arguments in Special Relativity Nicolaas Vroom <nicolaas.vroom@pandora.be> - 2017-06-22 03:47 -0700
                Re: Valid and Invalid Arguments in Special Relativity mlwozniak@wp.pl - 2017-06-22 04:16 -0700
                Re: Valid and Invalid Arguments in Special Relativity Gary Harnagel <hitlong@yahoo.com> - 2017-06-22 06:17 -0700
                Re: Valid and Invalid Arguments in Special Relativity mlwozniak@wp.pl - 2017-06-22 06:40 -0700
                Re: Valid and Invalid Arguments in Special Relativity Nicolaas Vroom <nicolaas.vroom@pandora.be> - 2017-06-23 02:30 -0700
                Re: Valid and Invalid Arguments in Special Relativity mlwozniak@wp.pl - 2017-06-23 03:49 -0700
                Re: Valid and Invalid Arguments in Special Relativity Odd Bodkin <bodkinodd@gmail.com> - 2017-06-23 07:32 -0500
                Re: Valid and Invalid Arguments in Special Relativity mlwozniak@wp.pl - 2017-06-23 05:53 -0700
                Re: Valid and Invalid Arguments in Special Relativity Gary Harnagel <hitlong@yahoo.com> - 2017-06-23 06:38 -0700
                Re: Valid and Invalid Arguments in Special Relativity Valok Planek <lkupuu@kwklewan.oo> - 2017-06-24 10:27 +0000
              Re: Valid and Invalid Arguments in Special Relativity Tom Roberts <tjroberts137@sbcglobal.net> - 2017-06-23 09:43 -0500
      Re: Valid and Invalid Arguments in Special Relativity Odd Bodkin <bodkinodd@gmail.com> - 2017-06-20 11:20 +0000
        Re: Valid and Invalid Arguments in Special Relativity Ned Latham <nedlatham@woden.valhalla.oz> - 2017-06-20 06:54 -0500
          Re: Valid and Invalid Arguments in Special Relativity Odd Bodkin <bodkinodd@gmail.com> - 2017-06-20 08:29 -0500
            Re: Valid and Invalid Arguments in Special Relativity Ned Latham <nedlatham@woden.valhalla.oz> - 2017-06-20 09:17 -0500
              Re: Valid and Invalid Arguments in Special Relativity Odd Bodkin <bodkinodd@gmail.com> - 2017-06-21 11:12 -0500
              Re: Valid and Invalid Arguments in Special Relativity Odd Bodkin <bodkinodd@gmail.com> - 2017-06-21 17:11 +0000
      Re: Valid and Invalid Arguments in Special Relativity Tom Roberts <tjroberts137@sbcglobal.net> - 2017-06-20 09:03 -0500
        Re: Valid and Invalid Arguments in Special Relativity Ned Latham <nedlatham@woden.valhalla.oz> - 2017-06-20 10:24 -0500
          Re: Valid and Invalid Arguments in Special Relativity Eshiki Orakut <usa@iwikuh.ki> - 2017-06-20 16:54 +0000
          Re: Valid and Invalid Arguments in Special Relativity Tom Roberts <tjroberts137@sbcglobal.net> - 2017-06-20 20:05 -0500
    Re: Valid and Invalid Arguments in Special Relativity Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-06-20 18:56 +0200
      Re: Valid and Invalid Arguments in Special Relativity Tom Roberts <tjroberts137@sbcglobal.net> - 2017-06-20 20:17 -0500
        Re: Valid and Invalid Arguments in Special Relativity Eshiki Orakut <usa@iwikuh.ki> - 2017-06-21 09:38 +0000
  Re: Valid and Invalid Arguments in Special Relativity JanPB <filmart@gmail.com> - 2017-06-20 02:48 -0700
    Re: Valid and Invalid Arguments in Special Relativity Eshiki Orakut <usa@iwikuh.ki> - 2017-06-20 13:05 +0000

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