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Re: The Secret to Einstein's Twin Paradox

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Tom Roberts wrote:

> On 6/29/17 6/29/17   7:41 AM, Thomas 'PointedEars' Lahn wrote:
>> Tom Roberts wrote:
>>>  From that information the observer knows the sender's age when the
>>>  signal
>>> was SENT, without reference to the CADO frame. But from that information
>>> alone the observer cannot possibly know how old she is when it is
>>> RECEIVED.
>>> Because this is not a measurement of the distant person, it is a
>>> measurement of a SIGNAL, and the observer does not know how long the
>>> signal traveled from her to him.
>> 
>> I presume it could be calculated if the sender time would be encoded in
>> the signal (as with GPS), but it would only be trivial to do in flat
>> spacetime and non-complex (e.g., one-time) acceleration (as in the twin
>> paradox).
> 
> The sender's age is part of the signal, as Mike stated. But your
> PRESUMPTION that the receiver could calculate the time the signal was in
> transit is precisely at issue -- for arbitrary motion of the observer it
> cannot be done (except for the case of my exception, using the inertial
> frame, as the GPS does).

In flat spacetime:

Suppose the receiver would synchronize their clock with the sender when the 
former is at relative rest to the latter, and the sender would from then on 
send a signal to the receiver all the times, so that the initial distance to 
the receiver could be determined by subtracting light travel time.

Could the receiver determine from the Doppler shift of the signal at all 
times what their velocity relative to the sender is at all times (so even 
when accelerating), and from the information in the signals, do the Lorentz 
transformation to obtain the sender’s current spacetime position (assuming 
that the sender still exists)?
 
-- 
PointedEars

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

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The Secret to Einstein's Twin Paradox Pentcho Valev <pvalev@yahoo.com> - 2017-06-19 14:30 -0700
  Re: The Secret to Einstein's Twin Paradox Gary Harnagel <hitlong@yahoo.com> - 2017-06-19 14:48 -0700
    Re: The Secret to Einstein's Twin Paradox Eshiki Orakut <usa@iwikuh.ki> - 2017-06-20 13:45 +0000
      Re: The Secret to Einstein's Twin Paradox Mike Fontenot <mlfasf@comcast.net> - 2017-06-20 09:49 -0600
        Re: The Secret to Einstein's Twin Paradox Eshiki Orakut <usa@iwikuh.ki> - 2017-06-20 21:10 +0000
        Re: The Secret to Einstein's Twin Paradox mlwozniak@wp.pl - 2017-06-21 02:40 -0700
          Re: The Secret to Einstein's Twin Paradox JanPB <filmart@gmail.com> - 2017-06-23 04:42 -0700
            Re: The Secret to Einstein's Twin Paradox mlwozniak@wp.pl - 2017-06-23 04:48 -0700
              Re: The Secret to Einstein's Twin Paradox JanPB <filmart@gmail.com> - 2017-06-23 13:51 -0700
        Re: The Secret to Einstein's Twin Paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-06-22 04:30 -0700
          Re: The Secret to Einstein's Twin Paradox JanPB <filmart@gmail.com> - 2017-06-23 04:44 -0700
            Re: The Secret to Einstein's Twin Paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-06-27 07:06 -0700
              Re: The Secret to Einstein's Twin Paradox Mike Fontenot <mlfasf@comcast.net> - 2017-06-27 12:22 -0600
                Re: The Secret to Einstein's Twin Paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-06-27 22:44 -0500
                Re: The Secret to Einstein's Twin Paradox Mike Fontenot <mlfasf@comcast.net> - 2017-06-28 07:40 -0600
                Re: The Secret to Einstein's Twin Paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-06-29 00:26 -0500
                Re: The Secret to Einstein's Twin Paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-06-29 04:01 -0700
                Re: The Secret to Einstein's Twin Paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-06-29 04:14 -0700
                Re: The Secret to Einstein's Twin Paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-06-29 08:30 -0500
                Re: The Secret to Einstein's Twin Paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-06-29 06:54 -0700
                Re: The Secret to Einstein's Twin Paradox Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-06-29 14:41 +0200
                Re: The Secret to Einstein's Twin Paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-06-29 08:37 -0500
                Re: The Secret to Einstein's Twin Paradox Poutnik <poutnik4nntp@gmail.com> - 2017-06-29 16:16 +0200
                Re: The Secret to Einstein's Twin Paradox Jim Petroff <ruuri@twjotr.eo> - 2017-06-29 14:29 +0000
                Re: The Secret to Einstein's Twin Paradox Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-06-29 16:45 +0200
                Re: The Secret to Einstein's Twin Paradox Jim Petroff <ruuri@twjotr.eo> - 2017-06-29 15:00 +0000
                Re: The Secret to Einstein's Twin Paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-06-29 08:11 -0700
                Re: The Secret to Einstein's Twin Paradox Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-06-29 17:19 +0200
                Re: The Secret to Einstein's Twin Paradox Jim Petroff <ruuri@twjotr.eo> - 2017-06-29 15:34 +0000
                Re: The Secret to Einstein's Twin Paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-06-29 08:39 -0700
                Re: The Secret to Einstein's Twin Paradox Jim Petroff <ruuri@twjotr.eo> - 2017-06-29 15:29 +0000
                Re: The Secret to Einstein's Twin Paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-07-01 12:29 -0500
                Re: The Secret to Einstein's Twin Paradox Mike Fontenot <mlfasf@comcast.net> - 2017-07-02 12:35 -0600
                Re: The Secret to Einstein's Twin Paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-07-03 08:18 -0700
                Re: The Secret to Einstein's Twin Paradox Mike Fontenot <mlfasf@comcast.net> - 2017-07-03 09:45 -0600
                Re: The Secret to Einstein's Twin Paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-07-04 05:24 -0700
                Re: The Secret to Einstein's Twin Paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-07-03 17:52 -0500
                Re: The Secret to Einstein's Twin Paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-07-04 05:45 -0700
                Re: The Secret to Einstein's Twin Paradox Poutnik <poutnik4nntp@gmail.com> - 2017-07-04 15:03 +0200
                Re: The Secret to Einstein's Twin Paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-07-07 13:56 -0700
                Re: The Secret to Einstein's Twin Paradox Poutnik <poutnik4nntp@gmail.com> - 2017-07-07 23:55 +0200
                Re: The Secret to Einstein's Twin Paradox mlwozniak@wp.pl - 2017-07-08 00:15 -0700
                Re: The Secret to Einstein's Twin Paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-07-10 08:43 -0700
                Re: The Secret to Einstein's Twin Paradox Upech Bezradne <adeeia@bbzzeop.ic> - 2017-07-08 10:44 +0000
                Re: The Secret to Einstein's Twin Paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-07-10 08:38 -0700
                Re: The Secret to Einstein's Twin Paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-07-04 12:56 -0500
                Re: The Secret to Einstein's Twin Paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-07-07 13:20 -0700
                Re: The Secret to Einstein's Twin Paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-07-08 00:06 -0500
                Re: The Secret to Einstein's Twin Paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-07-10 08:26 -0700
                Re: The Secret to Einstein's Twin Paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-07-11 10:56 -0500
                Re: The Secret to Einstein's Twin Paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-07-11 13:40 -0700
                Re: The Secret to Einstein's Twin Paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-07-12 10:13 -0500
                Re: The Secret to Einstein's Twin Paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-07-13 10:07 -0700
                Re: The Secret to Einstein's Twin Paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-07-14 20:04 -0500
                Re: The Secret to Einstein's Twin Paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-07-15 13:49 -0700
                Re: The Secret to Einstein's Twin Paradox The Starmaker <starmaker@ix.netcom.com> - 2017-07-15 14:26 -0700
                Re: The Secret to Einstein's Twin Paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-07-17 20:20 -0500
                Re: The Secret to Einstein's Twin Paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-07-20 07:25 -0700
                Re: The Secret to Einstein's Twin Paradox kenseto <setoken@att.net> - 2017-07-05 07:50 -0700
                Re: The Secret to Einstein's Twin Paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-07-03 18:26 -0500
                Re: The Secret to Einstein's Twin Paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-06-29 07:05 -0700
                Re: The Secret to Einstein's Twin Paradox Mike Fontenot <mlfasf@comcast.net> - 2017-06-29 09:31 -0600
                Re: The Secret to Einstein's Twin Paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-06-28 05:01 -0700
                Re: The Secret to Einstein's Twin Paradox Mike Fontenot <mlfasf@comcast.net> - 2017-06-28 07:52 -0600
                Re: The Secret to Einstein's Twin Paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-06-29 03:47 -0700
                Re: The Secret to Einstein's Twin Paradox Mike Fontenot <mlfasf@comcast.net> - 2017-06-29 10:19 -0600
                Re: The Secret to Einstein's Twin Paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-06-30 08:09 -0700
                Re: The Secret to Einstein's Twin Paradox Lord Kronos Prime <fuller.david@hotmail.com> - 2017-06-30 08:39 -0700
                Re: The Secret to Einstein's Twin Paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-07-01 08:33 -0700
                Re: The Secret to Einstein's Twin Paradox Mike Fontenot <mlfasf@comcast.net> - 2017-06-30 11:30 -0600
                Re: The Secret to Einstein's Twin Paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-07-01 08:11 -0700
  Re: The Secret to Einstein's Twin Paradox Pentcho Valev <pvalev@yahoo.com> - 2017-06-19 23:58 -0700
  Re: The Secret to Einstein's Twin Paradox JanPB <filmart@gmail.com> - 2017-06-20 03:18 -0700
    Re: The Secret to Einstein's Twin Paradox Lipek Mniak <iluka@sskwpiw.pp> - 2017-06-23 11:47 +0000
      Re: The Secret to Einstein's Twin Paradox The Starmaker <starmaker@ix.netcom.com> - 2017-06-23 11:18 -0700
  Re: The Secret to Einstein's Twin Paradox Eckard B <eckard.blumschein@arcor.de> - 2017-06-21 09:21 -0700
    Re: The Secret to Einstein's Twin Paradox Poutnik <poutnik4nntp@gmail.com> - 2017-06-21 19:33 +0200
      Re: The Secret to Einstein's Twin Paradox Poutnik <poutnik4nntp@gmail.com> - 2017-06-22 07:32 +0200
        Re: The Secret to Einstein's Twin Paradox mlwozniak@wp.pl - 2017-06-21 23:16 -0700
        Re: The Secret to Einstein's Twin Paradox Lipek Mniak <iluka@sskwpiw.pp> - 2017-06-23 11:33 +0000
      Re: The Secret to Einstein's Twin Paradox Eckard B <eckard.blumschein@arcor.de> - 2017-06-22 08:14 -0700
        Re: The Secret to Einstein's Twin Paradox Poutnik <poutnik4nntp@gmail.com> - 2017-06-22 18:13 +0200
          Re: The Secret to Einstein's Twin Paradox Lipek Mniak <iluka@sskwpiw.pp> - 2017-06-23 11:35 +0000
            Re: The Secret to Einstein's Twin Paradox The Starmaker <starmaker@ix.netcom.com> - 2017-06-23 11:15 -0700
        Re: The Secret to Einstein's Twin Paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-06-22 15:38 -0500
          Re: The Secret to Einstein's Twin Paradox Eckard B <eckard.blumschein@arcor.de> - 2017-06-23 03:22 -0700
            Re: The Secret to Einstein's Twin Paradox Lipek Mniak <iluka@sskwpiw.pp> - 2017-06-23 11:38 +0000
            Re: The Secret to Einstein's Twin Paradox Poutnik <poutnik4nntp@gmail.com> - 2017-06-28 08:32 +0200
          Re: The Secret to Einstein's Twin Paradox mlwozniak@wp.pl - 2017-06-23 03:37 -0700
  Re: The Secret to Einstein's Twin Paradox bigal95210@gmail.com - 2017-06-21 16:48 -0700
    Re: The Secret to Einstein's Twin Paradox John Gogo <jfgogo22@yahoo.com> - 2017-07-14 19:00 -0700
  Re: The Secret to Einstein's Twin Paradox Lipek Mniak <iluka@sskwpiw.pp> - 2017-06-23 11:43 +0000

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