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Re: Question....Good Question.

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On 21/08/16 21:31, Paul B. Andersen wrote:
> On 21.08.2016 11:28, HGWilson, DSc. wrote:
>> On 21/08/16 17:07, Paul B. Andersen wrote:
>
>>>> Since the same people claim that light moves at c relative to the
>>>> Earth's ECI frame, rather than to its source,
>>>
>>> Some ignorant people claim that SR say that light moves at
>>> c relative to the Earth's ECI frame, _rather than to its source_.
>
> The point which some ignorant people may have managed to miss is:
>
> The statement:
>   "Since the same people claim that light moves at c relative
>    to the Earth's ECI frame, rather than to its source"
> suggests that "the same people" claim that the speed of light
> is not c relative to its source which is moving in the ECI frame.
>
> But "the same people" don't claim that. They claim:
>
>    The speed of light is isotropic c in the ECI frame,
>    _and_ it is isotropic c in the momentarily comoving inertial
>    frame of the source.
>
> Or more loosely:
>
>    Light moves at c relative to the Earth's ECI frame,
>    AND it moves at c relative to its source.

To an observer at rest in the earth's ECI frame, the light moves at c+v 
relative to the source. (as illustrated in a ring gyro for instance 
where the two beams depart the source at c+v and c-v in the non-rotating 
frame.)
...but the sun's ECI frame, is moving relative to the Earth's...so an 
observer at rest in the Sun's frame will see it depart at c+u.
How does the light know in which of the two frames is it supposed to 
move at c?
If you are now going to say simply that it always moves at c in any 
frame, and that an observer at rest in either the sun's or the Earth's 
ECI frame will see a light pulse departing from its source at the same 
c+x then all that crap about the GPS signals moving at c in the Earth's 
ECI frame is completely irrelevant. There is nothing special about any 
ECI frame.


>> Here is a quote from Tom Roberts, today: The GPS demonstrates that the
>> vacuum speed of light is isotropically c in the ECI frame, which is the
>> LOCALLY inertial frame centered on the earth (so it does not rotate with
>> the planet, but does orbit the sun with it).
>
> Quite.
> The GPS is another ever ongoing experiment which
> is confirming that the speed of light is isotropically c
> in the ECI frame.

That's what Ken Seto says...and you all laugh at him.

>> Are you agreeing that Tom sprouts endless bullshit?...or is it you who
>> does?
>
> After 35+ years of operation of the GPS Tom's statement above
> is a trivial truth, so what is your point?
>
>>>
>>>> does this not mean that a
>>>> rod standardized at the equator would have a different length depending
>>>> on the direction used in the measuring procedure?
>>>
>>> Yes, that does not mean this.
>>
>> According to Tom Roberts, you are talking bullshit.
>
> Good grief. :-D
> You are actually claiming that Tom would say
> I am talking bullshit when I claim that according
> to SR the speed of light in vacuum is invariant!

Light has no 'speed' in vacuum or anything else. All speeds are relative.

> Congratulation, Ralph.

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Thread

Question....Good Question. "HGWilson, DSc." <hgw@....> - 2016-08-21 09:19 +1000
  Re: Question....Good Question. benj <benj@nobody.net> - 2016-08-20 21:12 -0400
    Re: Question....Good Question. Tom Roberts <tjroberts137@sbcglobal.net> - 2016-08-20 22:28 -0500
  Re: Question....Good Question. "Paul B. Andersen" <relativity@paulba.no> - 2016-08-21 09:07 +0200
    Re: Question....Good Question. "HGWilson, DSc." <hgw@....> - 2016-08-21 19:28 +1000
      Re: Question....Good Question. "Paul B. Andersen" <relativity@paulba.no> - 2016-08-21 13:31 +0200
        Re: Question....Good Question. "HGWilson, DSc." <hgw@....> - 2016-08-22 07:20 +1000
          Re: Question....Good Question. Rafael Valls Hidalgo-Gato <rvalls162@gmail.com> - 2016-08-22 05:38 -0700
            Re: Question....Good Question. "HGWilson, DSc." <hgw@....> - 2016-08-23 05:46 +1000
              Re: Question....Good Question. Rafael Valls Hidalgo-Gato <rvalls162@gmail.com> - 2016-08-22 14:30 -0700
                Re: Question....Good Question. "HGW." <hw@....> - 2016-08-23 08:11 +1000
                Re: Question....Good Question. Gary Harnagel <hitlong@yahoo.com> - 2016-08-22 18:41 -0700
          Re: Question....Good Question. "Paul B. Andersen" <relativity@paulba.no> - 2016-08-22 23:07 +0200
      Re: Question....Good Question. Tom Roberts <tjroberts137@sbcglobal.net> - 2016-08-23 09:35 -0500
    Re: Question....Good Question. Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-08-21 11:48 +0200
      Re: Question....Good Question. "Paul B. Andersen" <relativity@paulba.no> - 2016-08-21 14:05 +0200
      Re: Question....Good Question. "HGWilson, DSc." <hgw@....> - 2016-08-22 07:22 +1000

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