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Re: Separation of Accelerating Observers in Special Relativity

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On 12/20/23 10:29 PM, Tom Roberts wrote:

>> On 12/20/23 11:44 AM, Tom Roberts wrote:
>>> Assuming the person on the trailing rocket measures the separation
>>>  simultaneously in their successive instantaneously co-moving 
>>> inertial frames, that separation MUST successively increase.

I (Mike Fontenot) respond:

The person on the trailing rocket would want NOTHING to do with the 
momentarily co-moving inertial person (the MCMIP) or what the MCMIP says 
about the separation of the rockets:  that person says that the rockets 
started their engines at different times ... the accelerating trailing 
person says the rockets were fired at the same instant.

And then I (MLF) said:

>>
>> That's NOT the way person on the trailing rocket measures the 
>> separation!  He measures the separation with a tape measure, and
>> THAT shows the separation is constant.

And Tom Roberts (TR) responded:
> 
> WHAT tape measure? -- none is specified in the problem.
> 

If the two people on the two rockets want to run a tape measure between 
their rockets, they can do it.  Since I'm interested in the trailing 
person's conclusions about their separation, I'll assume that the end of 
the tape is attached to the tail-end of leading rocket, and that the 
CASE of the measuring tape is attached to the front-end of the trailing 
rocket, so that the tape is free to slide in or out of the case.

Tom wrote:

> the leading rocket
> has a larger proper acceleration than the leading end of the tape
> measure, and thus pulls away from it.

And I (Mike) responded:

That's ridiculous.  The spring tension inside the case of the tape 
measure is small, and certainly doesn't pull the end of the tape away 
from the leading rocket, where it is firmly attached.

Then Tom said:

> So the tape measure shows the
> separation is increasing.

And I (Mike) respond:

No, it doesn't.  The accelerometers on the two rockets show the same 
(constant) readings, and that results in the separation between the 
rockets being constant, and the tape measure showing a constant reading.

Then Tom said:

> Or why he (Mike) ignores the voluminous
> literature on this.

The primary relevant literature for this discussion is the Wiki page on 
Bell's Spaceship Paradox, and that webpage is a great example of "too 
many cooks spoiling the broth" ... it's a collection of multiple 
statements that are mutually inconsistent.  For example, they say that 
the initial inertial observers will observe the separation of the 
accelerating rockets to be constant.  The length contraction equation 
(LCE) says that if a yardstick is moving away from an inertial observer, 
the inertial observer will conclude that the length of the yardstick has 
gotten smaller at any instant by the factor gamma (where gamma is a 
function of speed, and increases with speed).  So that means that if the 
initial inertial observers say the rocket separation is constant, then 
the two rockets must actually be getting farther apart (as measured in 
the frame of the person on the trailing rocket).  And THAT means that 
the two accelerometers CAN'T be showing the same readings: the leading 
rocket is accelerating faster than the trailing rocket. So when the Wiki 
article claims that the initial inertial observers say the separation is 
constant, AND that the accelerometers show the same readings (i.e., that 
the rockets "are identical"), they are being inconsistent. If the 
initial inertial observers say the separation of the rockets is 
constant, then the separation of the rockets, according to the people on 
the trailing rocket, is increasing, and the leading accelerometer will 
read higher that the trailing accelerometer.

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Separation of Accelerating Observers in Special Relativity Mike Fontenot <mlfasf@comcast.net> - 2023-12-17 17:46 -0700
  Re: Separation of Accelerating Observers in Special Relativity Tom Roberts <tjoberts137@sbcglobal.net> - 2023-12-18 21:12 -0600
    Re: Separation of Accelerating Observers in Special Relativity Mike Fontenot <mlfasf@comcast.net> - 2023-12-19 09:06 -0700
      Re: Separation of Accelerating Observers in Special Relativity RichD <r_delaney2001@yahoo.com> - 2023-12-19 16:30 -0800
  Re: Separation of Accelerating Observers in Special Relativity Mikko <mikko.levanto@iki.fi> - 2023-12-19 12:25 +0200
  Re: Separation of Accelerating Observers in Special Relativity RichD <r_delaney2001@yahoo.com> - 2023-12-19 16:46 -0800
    Re: Separation of Accelerating Observers in Special Relativity Samille Bass <sble@bsslsmaa.ib> - 2023-12-20 01:27 +0000
    Re: Separation of Accelerating Observers in Special Relativity Tom Roberts <tjoberts137@sbcglobal.net> - 2023-12-20 12:44 -0600
      Re: Separation of Accelerating Observers in Special Relativity Mike Fontenot <mlfasf@comcast.net> - 2023-12-20 12:06 -0700
        Re: Separation of Accelerating Observers in Special Relativity Tom Roberts <tjoberts137@sbcglobal.net> - 2023-12-20 23:29 -0600
          Re: Separation of Accelerating Observers in Special Relativity Mike Fontenot <mlfasf@comcast.net> - 2023-12-21 12:48 -0700
            Re: Separation of Accelerating Observers in Special Relativity Tom Roberts <tjoberts137@sbcglobal.net> - 2023-12-23 14:42 -0600
              Re: Separation of Accelerating Observers in Special Relativity Mike Fontenot <mlfasf@comcast.net> - 2023-12-23 17:13 -0700
                Re: Separation of Accelerating Observers in Special Relativity Tom Roberts <tjoberts137@sbcglobal.net> - 2023-12-24 11:31 -0600
                Re: Separation of Accelerating Observers in Special Relativity Ross Finlayson <ross.a.finlayson@gmail.com> - 2023-12-24 10:48 -0800
                Re: Separation of Accelerating Observers in Special Relativity Ross Finlayson <ross.a.finlayson@gmail.com> - 2023-12-24 12:03 -0800
                Re: Separation of Accelerating Observers in Special Relativity Ross Finlayson <ross.a.finlayson@gmail.com> - 2023-12-25 00:38 -0800
                Re: Separation of Accelerating Observers in Special Relativity Ross Finlayson <ross.a.finlayson@gmail.com> - 2023-12-26 10:21 -0800
                Re: Separation of Accelerating Observers in Special Relativity Ross Finlayson <ross.a.finlayson@gmail.com> - 2023-12-27 10:20 -0800
                Re: Separation of Accelerating Observers in Special Relativity Ross Finlayson <ross.a.finlayson@gmail.com> - 2023-12-27 12:08 -0800
                Re: Separation of Accelerating Observers in Special Relativity Ross Finlayson <ross.a.finlayson@gmail.com> - 2023-12-30 00:56 -0800
                Re: Separation of Accelerating Observers in Special Relativity Ross Finlayson <ross.a.finlayson@gmail.com> - 2024-01-01 14:47 -0800
                Re: Separation of Accelerating Observers in Special Relativity Maciej Wozniak <maluwozniak@gmail.com> - 2024-01-01 21:12 -0800
                Re: Separation of Accelerating Observers in Special Relativity Ross Finlayson <ross.a.finlayson@gmail.com> - 2024-01-01 22:27 -0800
                Re: Separation of Accelerating Observers in Special Relativity Maciej Wozniak <maluwozniak@gmail.com> - 2024-01-01 22:58 -0800
                Re: Separation of Accelerating Observers in Special Relativity Mike Fontenot <mlfasf@comcast.net> - 2023-12-24 12:14 -0700
                Re: Separation of Accelerating Observers in Special Relativity Tom Roberts <tjoberts137@sbcglobal.net> - 2023-12-24 15:13 -0600
                Re: Separation of Accelerating Observers in Special Relativity Mike Fontenot <mlfasf@comcast.net> - 2023-12-25 11:04 -0700
                Re: Separation of Accelerating Observers in Special Relativity Tom Roberts <tjoberts137@sbcglobal.net> - 2023-12-25 13:38 -0600
                Re: Separation of Accelerating Observers in Special Relativity Mike Fontenot <mlfasf@comcast.net> - 2023-12-25 13:25 -0700
                Re: Separation of Accelerating Observers in Special Relativity Tom Roberts <tjoberts137@sbcglobal.net> - 2023-12-25 23:56 -0600
                Re: Separation of Accelerating Observers in Special Relativity Mike Fontenot <mlfasf@comcast.net> - 2023-12-26 09:52 -0700
                Re: Separation of Accelerating Observers in Special Relativity Tom Roberts <tjoberts137@sbcglobal.net> - 2023-12-26 15:38 -0600
                Re: Separation of Accelerating Observers in Special Relativity Maciej Wozniak <maluwozniak@gmail.com> - 2023-12-26 22:35 -0800
                Re: Separation of Accelerating Observers in Special Relativity Mike Fontenot <mlfasf@comcast.net> - 2023-12-27 06:51 -0700
                Re: Separation of Accelerating Observers in Special Relativity Maciej Wozniak <maluwozniak@gmail.com> - 2023-12-27 06:03 -0800
                Re: Separation of Accelerating Observers in Special Relativity rotchm <rotchm@gmail.com> - 2023-12-27 06:26 -0800
                Re: Separation of Accelerating Observers in Special Relativity Maciej Wozniak <maluwozniak@gmail.com> - 2023-12-27 06:34 -0800
                Re: Separation of Accelerating Observers in Special Relativity Tom Roberts <tjoberts137@sbcglobal.net> - 2023-12-27 08:39 -0600
                Re: Separation of Accelerating Observers in Special Relativity Maciej Wozniak <maluwozniak@gmail.com> - 2023-12-27 07:03 -0800
                Re: Separation of Accelerating Observers in Special Relativity Mike Fontenot <mlfasf@comcast.net> - 2023-12-27 13:29 -0700
                Re: Separation of Accelerating Observers in Special Relativity Ross Finlayson <ross.a.finlayson@gmail.com> - 2023-12-27 21:14 -0800
                Re: Separation of Accelerating Observers in Special Relativity Mike Fontenot <mlfasf@comcast.net> - 2023-12-30 13:40 -0700
                Re: Separation of Accelerating Observers in Special Relativity Tom Roberts <tjoberts137@sbcglobal.net> - 2024-01-01 17:32 -0600
                Re: Separation of Accelerating Observers in Special Relativity Maciej Wozniak <maluwozniak@gmail.com> - 2024-01-01 21:11 -0800
                Re: Separation of Accelerating Observers in Special Relativity Mike Fontenot <mlfasf@comcast.net> - 2024-01-02 09:28 -0700
                Re: Separation of Accelerating Observers in Special Relativity Ross Finlayson <ross.a.finlayson@gmail.com> - 2024-01-02 13:14 -0800
                Re: Separation of Accelerating Observers in Special Relativity Tom Roberts <tjoberts137@sbcglobal.net> - 2024-01-01 11:42 -0600
                Re: Separation of Accelerating Observers in Special Relativity Mike Fontenot <mlfasf@comcast.net> - 2024-01-01 10:58 -0700
                Re: Separation of Accelerating Observers in Special Relativity Tom Roberts <tjoberts137@sbcglobal.net> - 2024-01-01 12:07 -0600
                Re: Separation of Accelerating Observers in Special Relativity RichD <r_delaney2001@yahoo.com> - 2023-12-28 19:16 -0800
                Re: Separation of Accelerating Observers in Special Relativity rotchm <rotchm@gmail.com> - 2023-12-26 13:48 -0800
                Re: Separation of Accelerating Observers in Special Relativity Mike Fontenot <mlfasf@comcast.net> - 2023-12-26 10:12 -0700
                Re: Separation of Accelerating Observers in Special Relativity Volney <volney@invalid.invalid> - 2023-12-25 21:41 -0500
              Re: Separation of Accelerating Observers in Special Relativity Maciej Wozniak <maluwozniak@gmail.com> - 2023-12-25 04:32 -0800
          Re: Separation of Accelerating Observers in Special Relativity Mikko <mikko.levanto@iki.fi> - 2023-12-22 16:29 +0200
          Re: Separation of Accelerating Observers in Special Relativity whodat <whodaat@void.nowgre.com> - 2023-12-22 15:53 -0600

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