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Re: Bell's spaceship paradox...

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Tom Roberts schreef op 7/09/2015 om 19:50:
> On 9/7/15 9/7/15   11:30 AM, wugi wrote:
>> Time and again I see this confusion of distance assessment. (...)
>
> Yes. The relativity of simultaneity is important in these scenarios.
>
>
>> First, it makes one realise that, generally, strong (relativistically
>> speaking)
>> acceleration will not leave the inner structure of an object
>> (spaceship, or rope
>> between spaceships...) unstressed, internally that is. (...)
>
> Yes. And different patterns of strain as well.

Well, by stress I suppose I meant stress and strain. I thought "stress" 
covers both, as in stress tensor, stress mechanics...

> It is common in relativistic gedankens to ignore material properties,
> including stresses and strains within objects. Because they generally do
> not contribute to the issues being discussed.
>
>
>> I seem to have read that unstressed (co-ordinated) forms of
>> acceleration exist,
>> or are studied, but I forgot where. (At any moment the object should
>> find itself
>> having constant length L0 in its local inertial frame).
>
> Born rigid motion is defined as accelerating an object such that all
> proper lengths between its components remain fixed. This basically
> requires coupling the accelerating force to each and every component of
> the object.

Yes, that was it. Unrealistic, even in this unrealistic scenario of 
organising "rigid relativistic acceleration" ;-)

> Ordinary (rigid) objects under ordinary accelerations approximately
> achieve Born rigid motion [#], because the inter-atomic forces are much
> stronger than the accelerating force. But ordinary accelerations are
> usually insufficient to achieve relativistic speeds in gedankens.
>
>      [#] A 110 meter Saturn V rocket gets a few cm shorter during
>      launch, less than a part per thousand.

Which by itself I find quite a lot: a mm or two for an adult (save that 
he would be lying down:). But I understand that this concerns ordinary 
stresses, not relativistic ones...

-- 
guido

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Bell's spaceship paradox... rotchm <rotchm@gmail.com> - 2015-09-02 20:32 -0700
  Re: Bell's spaceship paradox... "Paul B. Andersen" <relativity@paulba.no> - 2015-09-03 11:27 +0200
  Re: Bell's spaceship paradox... alsor@interia.pl - 2015-09-03 08:32 -0700
    Re: Bell's spaceship paradox... JanPB <filmart@gmail.com> - 2015-09-03 09:44 -0700
      Re: Bell's spaceship paradox... alsor@interia.pl - 2015-09-03 10:23 -0700
        Re: Bell's spaceship paradox... JanPB <filmart@gmail.com> - 2015-09-03 12:07 -0700
          Re: Bell's spaceship paradox... alsor@interia.pl - 2015-09-03 12:13 -0700
            Re: Bell's spaceship paradox... JanPB <filmart@gmail.com> - 2015-09-03 12:39 -0700
              Re: Bell's spaceship paradox... "Lleyton H. Bellucci" <lleyb@stratospheree.org> - 2015-09-03 19:45 +0000
                Re: Bell's spaceship paradox... JanPB <filmart@gmail.com> - 2015-09-03 12:47 -0700
                Re: Bell's spaceship paradox... "Lleyton H. Bellucci" <lleyb@stratospheree.org> - 2015-09-03 19:52 +0000
                Re: Bell's spaceship paradox... JanPB <filmart@gmail.com> - 2015-09-03 13:58 -0700
                Re: Bell's spaceship paradox... "Lleyton H. Bellucci" <lleyb@stratospheree.org> - 2015-09-03 22:03 +0000
                Re: Bell's spaceship paradox... JanPB <filmart@gmail.com> - 2015-09-03 16:52 -0700
              Re: Bell's spaceship paradox... alsor@interia.pl - 2015-09-03 12:55 -0700
                Re: Bell's spaceship paradox... JanPB <filmart@gmail.com> - 2015-09-03 13:59 -0700
                Re: Bell's spaceship paradox... Odd Bodkin <bodkinodd@gmail.com> - 2015-09-03 17:05 -0500
                Re: Bell's spaceship paradox... Tom Roberts <tjroberts137@sbcglobal.net> - 2015-09-04 09:55 -0500
                Re: Bell's spaceship paradox... Odd Bodkin <bodkinodd@gmail.com> - 2015-09-04 10:04 -0500
                Re: Bell's spaceship paradox... Tom Roberts <tjroberts137@sbcglobal.net> - 2015-09-04 12:50 -0500
                Re: Bell's spaceship paradox... Odd Bodkin <bodkinodd@gmail.com> - 2015-09-04 13:48 -0500
                Re: Bell's spaceship paradox... Koobee Wublee <koobee.wublee@gmail.com> - 2015-09-04 12:44 -0700
                Re: Bell's spaceship paradox... JanPB <filmart@gmail.com> - 2015-09-04 13:55 -0700
                Re: Bell's spaceship paradox... Maciej Woźniak <mlwozniak@wp.pl> - 2015-09-05 15:09 +0200
                Re: Bell's spaceship paradox... JanPB <filmart@gmail.com> - 2015-09-05 11:51 -0700
                Re: Bell's spaceship paradox... kefischer <emoneyjoe@iglou.com> - 2015-09-04 16:22 -0400
                Re: Bell's spaceship paradox... Robert Winn <rbwinn3@gmail.com> - 2015-09-06 21:59 -0700
                Re: Bell's spaceship paradox... rotchm <rotchm@gmail.com> - 2015-09-07 05:49 -0700
                Re: Bell's spaceship paradox... Robert Winn <rbwinn3@gmail.com> - 2015-09-07 09:04 -0700
                Re: Bell's spaceship paradox... rotchm <rotchm@gmail.com> - 2015-09-07 09:30 -0700
                Re: Bell's spaceship paradox... Robert Winn <rbwinn3@gmail.com> - 2015-09-09 02:41 -0700
                Re: Bell's spaceship paradox... rotchm <rotchm@gmail.com> - 2015-09-09 04:16 -0700
                Re: Bell's spaceship paradox... alsor@interia.pl - 2015-09-04 12:11 -0700
                Re: Bell's spaceship paradox... JanPB <filmart@gmail.com> - 2015-09-04 12:45 -0700
                Re: Bell's spaceship paradox... alsor@interia.pl - 2015-09-04 13:14 -0700
                Re: Bell's spaceship paradox... Tom Roberts <tjroberts137@sbcglobal.net> - 2015-09-05 10:30 -0500
                Re: Bell's spaceship paradox... "Lleyton H. Bellucci" <lleyb@stratospheree.org> - 2015-09-05 15:47 +0000
                Re: Bell's spaceship paradox... alsor@interia.pl - 2015-09-05 09:48 -0700
                Re: Bell's spaceship paradox... alsor@interia.pl - 2015-09-05 09:30 -0700
                Re: Bell's spaceship paradox... JanPB <filmart@gmail.com> - 2015-09-05 11:50 -0700
                Re: Bell's spaceship paradox... alsor@interia.pl - 2015-09-05 12:05 -0700
                Re: Bell's spaceship paradox... JanPB <filmart@gmail.com> - 2015-09-05 12:14 -0700
                Re: Bell's spaceship paradox... alsor@interia.pl - 2015-09-05 12:36 -0700
                Re: Bell's spaceship paradox... JanPB <filmart@gmail.com> - 2015-09-05 14:11 -0700
                Re: Bell's spaceship paradox... alsor@interia.pl - 2015-09-06 09:35 -0700
                Re: Bell's spaceship paradox... JanPB <filmart@gmail.com> - 2015-09-06 11:04 -0700
                Re: Bell's spaceship paradox... alsor@interia.pl - 2015-09-06 18:07 -0700
                Re: Bell's spaceship paradox... JanPB <filmart@gmail.com> - 2015-09-11 15:35 -0700
                Re: Bell's spaceship paradox... kenseto <setoken@att.net> - 2015-09-05 06:12 -0700
                Re: Bell's spaceship paradox... alsor@interia.pl - 2015-09-04 11:34 -0700
                Re: Bell's spaceship paradox... pnalsing@gmail.com - 2015-09-03 14:51 -0700
                Re: Bell's spaceship paradox... alsor@interia.pl - 2015-09-04 11:11 -0700
                Re: Bell's spaceship paradox... pnalsing@gmail.com - 2015-09-04 11:14 -0700
                Re: Bell's spaceship paradox... mabel <wugi@scarlet.be> - 2015-09-04 20:52 +0200
                Re: Bell's spaceship paradox... JanPB <filmart@gmail.com> - 2015-09-04 11:14 -0700
                Re: Bell's spaceship paradox... alsor@interia.pl - 2015-09-04 12:53 -0700
                Re: Bell's spaceship paradox... JanPB <filmart@gmail.com> - 2015-09-05 22:52 -0700
                Re: Bell's spaceship paradox... alsor@interia.pl - 2015-09-06 09:42 -0700
                Re: Bell's spaceship paradox... JanPB <filmart@gmail.com> - 2015-09-09 15:07 -0700
                Re: Bell's spaceship paradox... pnalsing@gmail.com - 2015-09-09 15:33 -0700
                Re: Bell's spaceship paradox... alsor@interia.pl - 2015-09-11 09:08 -0700
                Re: Bell's spaceship paradox... JanPB <filmart@gmail.com> - 2015-09-11 12:52 -0700
                Re: Bell's spaceship paradox... Maciej Woźniak <mlwozniak@wp.pl> - 2015-09-11 22:45 +0200
                Re: Bell's spaceship paradox... JanPB <filmart@gmail.com> - 2015-09-11 15:16 -0700
                Re: Bell's spaceship paradox... Maciej Woźniak <mlwozniak@wp.pl> - 2015-09-12 12:10 +0200
                Re: Bell's spaceship paradox... alsor@interia.pl - 2015-09-11 13:55 -0700
                Re: Bell's spaceship paradox... JanPB <filmart@gmail.com> - 2015-09-11 15:13 -0700
                Re: Bell's spaceship paradox... alsor@interia.pl - 2015-09-13 09:19 -0700
                Re: Bell's spaceship paradox... JanPB <filmart@gmail.com> - 2015-09-13 14:01 -0700
                Re: Bell's spaceship paradox... alsor@interia.pl - 2015-09-14 09:12 -0700
    Re: Bell's spaceship paradox... Tom Roberts <tjroberts137@sbcglobal.net> - 2015-09-03 12:47 -0500
      Re: Bell's spaceship paradox... alsor@interia.pl - 2015-09-03 11:51 -0700
        Re: Bell's spaceship paradox... JanPB <filmart@gmail.com> - 2015-09-03 12:41 -0700
          Re: Bell's spaceship paradox... alsor@interia.pl - 2015-09-03 13:00 -0700
      Re: Bell's spaceship paradox... Maciej Woźniak <mlwozniak@wp.pl> - 2015-09-03 21:48 +0200
      Re: Bell's spaceship paradox... wugi <brol@brol.be> - 2015-09-07 18:30 +0200
        Re: Bell's spaceship paradox... Tom Roberts <tjroberts137@sbcglobal.net> - 2015-09-07 12:50 -0500
          Re: Bell's spaceship paradox... alsor@interia.pl - 2015-09-07 12:55 -0700
          Re: Bell's spaceship paradox... wugi <brol@brol.be> - 2015-09-12 17:17 +0200
  Re: Bell's spaceship paradox... John Gogo <jfgogo22@yahoo.com> - 2015-09-04 17:49 -0700
    Re: Bell's spaceship paradox... John Gogo <jfgogo22@yahoo.com> - 2015-09-04 19:09 -0700
  Re: Bell's spaceship paradox... rotchm <rotchm@gmail.com> - 2015-09-05 20:53 -0700

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