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Re: Testing of SR mutual time dilation

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As I think about it some more, and after Tom's reply, I realize that the
GPS satellite issue is more than mutual time dilation, it's really a
"traveling twin" problem.  The GPS satellite, as it moves in orbit from,
say, directly overhead, around the world, and back to directly overhead,
is the traveling twin, while the ground clock is the stay-at-home twin.(*)
In this case the traveling twin doesn't go out, turn around (accelerating)
and come back, it's constantly accelerating in a circle.  I assume the
"traveling twin moves in a simple circle" problem has a relatively simple
solution but I don't know it offhand.  I assume that we can still take the
GR gravity time dilation (over one orbit's time), add it to the traveling
twin's age difference over one orbit and add them and still be "close
enough" to the actual GR solution.

(*)except the stay-at-home twin doesn't quite stay at home, the earth 
rotates, now I have to understand this stuff about the ECI frame, the
geoid etc. and how it changes everything. Now I have a headache.

Anyway...

kenseto <setoken@att.net> writes:

>On Thursday, October 15, 2015 at 1:30:41 PM UTC-4, Michael Moroney wrote:
>> kenseto <setoken@att.net> writes:

>> >No idiot....the satellite experienced acceleration when it launched into 
>> >orbit. So from the ground clock point of view it is running slower by a 
>> >factor of -7us/day running slow.
>> 
>> No, mutual time dilation is a function of the speed difference between the 
>> two clocks, not on any acceleration.

>This shows me that you don't understand what speed bewtween two clocks 
>means....There is no speed difference between the two clocks. 

Putting aside the question whether the motion of the GPS satellite makes
for a mutual time dilation problem, this is wrong, and absurdly so. Mutual
time dilation is when, in A's inertial frame, A sees B as moving and B's
clock as running slow, and in B's inertial frame, B sees A as moving and 
A's clock as running slow.  You should try to learn SR some day.

>> >No idiot.....the launch acceleration is what caused the earth clock 
>> >+7us/day running fast.
>> 
>> The launch acceleration is totally irrelevant (as long as it didn't break
>> the clock, of course).  It was in the past.  What matters is the current
>> speed difference and the gravitational potential difference.

>Acceleration does matter....the different GPS clock rate is due to 
>acceleration.

Not launch acceleration.  There is acceleration due to moving in a circle,
changing this from a mutual time dilation problem to a traveling twin
problem.

> Again there is no speed different between the two clocks.

In my initial statement (assuming inertial motion was valid, or at least
"valid enough"), there most certainly was a speed difference between the
two clocks.  From the ground the GPS is moving rapidly and the ground
stationary, while from the GPS, the GPS itself is stationary while the
ground is moving rapidly.  The orbital acceleration changes much.

>> Time dilation in SR (and GR) always means the moving clock appears to run
>> slower, never faster.  

>It appears that you don't know what time dilation means. Between two 
>clocks in relative motion the clock that accumulate clock seconds at a 
>slower rate is called time dilation.

In (inertial) motion in SR, each observer sees the other as moving, and
the other's clock as running slow.  Seeing the other's clock as running
slow is the definition of time dilation.  Each observer seeing the other's
clock as running slow is mutual time dilation.

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Thread

Testing of SR mutual time dilation kenseto <setoken@att.net> - 2015-10-12 06:25 -0700
  Re: Testing of SR mutual time dilation Euclid Baumann <eubaum@parallelnetwork.org> - 2015-10-12 13:43 +0000
    Re: Testing of SR mutual time dilation kenseto <setoken@att.net> - 2015-10-12 07:24 -0700
      Re: Testing of SR mutual time dilation Dirk Van de moortel <dirkvandemoortel@hotspam.not> - 2015-10-12 19:44 +0200
  Re: Testing of SR mutual time dilation Tom Roberts <tjroberts137@sbcglobal.net> - 2015-10-12 10:31 -0500
    Re: Testing of SR mutual time dilation Euclid Baumann <eubaum@parallelnetwork.org> - 2015-10-12 17:21 +0000
      Re: Testing of SR mutual time dilation Euclid Baumann <eubaum@parallelnetwork.org> - 2015-10-12 17:22 +0000
      Re: Testing of SR mutual time dilation Euclid Baumann <eubaum@parallelnetwork.org> - 2015-10-12 17:24 +0000
    Re: Testing of SR mutual time dilation Koobee Wublee <koobee.wublee@gmail.com> - 2015-10-12 10:35 -0700
    Re: Testing of SR mutual time dilation kenseto <setoken@att.net> - 2015-10-12 12:44 -0700
      Re: Testing of SR mutual time dilation Tom Roberts <tjroberts137@sbcglobal.net> - 2015-10-12 22:20 -0500
        Re: Testing of SR mutual time dilation kenseto <setoken@att.net> - 2015-10-14 05:57 -0700
          Re: Testing of SR mutual time dilation kefischer <emoneyjoe@iglou.com> - 2015-10-14 15:21 -0400
            Re: Testing of SR mutual time dilation kenseto <setoken@att.net> - 2015-10-14 12:49 -0700
        Re: Testing of SR mutual time dilation alsor@interia.pl - 2015-10-22 06:04 -0700
          Re: Testing of SR mutual time dilation JanPB <filmart@gmail.com> - 2015-10-22 11:22 -0700
    Re: Testing of SR mutual time dilation John Gogo <jfgogo22@yahoo.com> - 2015-10-12 21:23 -0700
      Re: Testing of SR mutual time dilation John Gogo <jfgogo22@yahoo.com> - 2015-10-12 21:28 -0700
  Re: Testing of SR mutual time dilation Odd Bodkin <bodkinodd@gmail.com> - 2015-10-12 10:40 -0500
    Re: Testing of SR mutual time dilation kenseto <setoken@att.net> - 2015-10-12 12:17 -0700
      Re: Testing of SR mutual time dilation John Heath <heathjohn2@gmail.com> - 2015-10-12 16:34 -0700
      Re: Testing of SR mutual time dilation Odd Bodkin <bodkinodd@gmail.com> - 2015-10-13 07:43 -0500
        Re: Testing of SR mutual time dilation kenseto <setoken@att.net> - 2015-10-14 05:37 -0700
          Re: Testing of SR mutual time dilation Gary Harnagel <hitlong@yahoo.com> - 2015-10-14 05:54 -0700
            Re: Testing of SR mutual time dilation kenseto <setoken@att.net> - 2015-10-14 12:58 -0700
              Re: Testing of SR mutual time dilation Gary Harnagel <hitlong@yahoo.com> - 2015-10-14 13:18 -0700
                Re: Testing of SR mutual time dilation kenseto <setoken@att.net> - 2015-10-15 06:35 -0700
                Re: Testing of SR mutual time dilation Gary Harnagel <hitlong@yahoo.com> - 2015-10-15 06:55 -0700
                Re: Testing of SR mutual time dilation Maciej Woźniak <mlwozniak@wp.pl> - 2015-10-15 17:46 +0200
              Re: Testing of SR mutual time dilation moroney@world.std.spaamtrap.com (Michael Moroney) - 2015-10-15 04:16 +0000
                Re: Testing of SR mutual time dilation kenseto <setoken@att.net> - 2015-10-15 06:01 -0700
                Re: Testing of SR mutual time dilation moroney@world.std.spaamtrap.com (Michael Moroney) - 2015-10-15 13:17 +0000
                Re: Testing of SR mutual time dilation kenseto <setoken@att.net> - 2015-10-15 09:12 -0700
                Re: Testing of SR mutual time dilation moroney@world.std.spaamtrap.com (Michael Moroney) - 2015-10-15 17:30 +0000
                Re: Testing of SR mutual time dilation Tom Roberts <tjroberts137@sbcglobal.net> - 2015-10-16 10:15 -0500
                Re: Testing of SR mutual time dilation Euclid Baumann <eubaum@parallelnetwork.org> - 2015-10-16 15:23 +0000
                Re: Testing of SR mutual time dilation Tom Roberts <tjroberts137@sbcglobal.net> - 2015-10-17 09:09 -0500
                Re: Testing of SR mutual time dilation Euclid Baumann <eubaum@parallelnetwork.org> - 2015-10-17 14:37 +0000
                Re: Testing of SR mutual time dilation Koobee Wublee <koobee.wublee@gmail.com> - 2015-10-16 09:50 -0700
                Re: Testing of SR mutual time dilation kenseto <setoken@att.net> - 2015-10-16 09:48 -0700
                Re: Testing of SR mutual time dilation moroney@world.std.spaamtrap.com (Michael Moroney) - 2015-10-16 18:06 +0000
                Re: Testing of SR mutual time dilation kefischer <emoneyjoe@iglou.com> - 2015-10-16 14:49 -0400
                Re: Testing of SR mutual time dilation Euclid Baumann <eubaum@parallelnetwork.org> - 2015-10-16 19:25 +0000
                Re: Testing of SR mutual time dilation Odd Bodkin <bodkinodd@gmail.com> - 2015-10-16 15:05 -0500
                Re: Testing of SR mutual time dilation Koobee Wublee <koobee.wublee@gmail.com> - 2015-10-16 13:14 -0700
                Re: Testing of SR mutual time dilation kefischer <emoneyjoe@iglou.com> - 2015-10-16 18:34 -0400
                Re: Testing of SR mutual time dilation Tom Roberts <tjroberts137@sbcglobal.net> - 2015-10-17 09:19 -0500
                Re: Testing of SR mutual time dilation Koobee Wublee <koobee.wublee@gmail.com> - 2015-10-17 12:25 -0700
                Re: Testing of SR mutual time dilation Tom Roberts <tjroberts137@sbcglobal.net> - 2015-10-17 11:15 -0500
                Re: Testing of SR mutual time dilation Maciej Woźniak <mlwozniak@wp.pl> - 2015-10-17 18:45 +0200
                Re: Testing of SR mutual time dilation alsor@interia.pl - 2015-10-22 07:39 -0700
                Re: Testing of SR mutual time dilation JanPB <filmart@gmail.com> - 2015-10-22 11:23 -0700
                Re: Testing of SR mutual time dilation John Gogo <jfgogo22@yahoo.com> - 2015-10-16 19:30 -0700
                Re: Testing of SR mutual time dilation fuller.david@hotmail.com - 2015-10-25 07:27 -0700
                Re: Testing of SR mutual time dilation fuller.david@hotmail.com - 2015-10-25 07:34 -0700
                Re: Testing of SR mutual time dilation Juan Esteban <esteju@freecannabis.org> - 2015-10-25 15:17 +0000
                Re: Testing of SR mutual time dilation fuller.david@hotmail.com - 2015-10-25 18:48 -0700
                Re: Testing of SR mutual time dilation fuller.david@hotmail.com - 2015-10-25 19:04 -0700
                Re: Testing of SR mutual time dilation Tom Roberts <tjroberts137@sbcglobal.net> - 2015-10-16 10:05 -0500
                Re: Testing of SR mutual time dilation Maciej Woźniak <mlwozniak@wp.pl> - 2015-10-16 18:14 +0200
                Re: Testing of SR mutual time dilation Koobee Wublee <koobee.wublee@gmail.com> - 2015-10-16 09:42 -0700
                Re: Testing of SR mutual time dilation kenseto <setoken@att.net> - 2015-10-16 10:04 -0700
                Re: Testing of SR mutual time dilation Tom Roberts <tjroberts137@sbcglobal.net> - 2015-10-17 09:29 -0500
                Re: Testing of SR mutual time dilation Maciej Woźniak <mlwozniak@wp.pl> - 2015-10-17 17:06 +0200
                Re: Testing of SR mutual time dilation kenseto <setoken@att.net> - 2015-10-18 09:07 -0700
          Re: Testing of SR mutual time dilation Odd Bodkin <bodkinodd@gmail.com> - 2015-10-14 08:50 -0500
          Re: Testing of SR mutual time dilation Tom Roberts <tjroberts137@sbcglobal.net> - 2015-10-14 22:19 -0500
            Re: Testing of SR mutual time dilation JanPB <filmart@gmail.com> - 2015-10-14 20:28 -0700
            Re: Testing of SR mutual time dilation kenseto <setoken@att.net> - 2015-10-15 06:20 -0700
            Re: Testing of SR mutual time dilation John Gogo <jfgogo22@yahoo.com> - 2015-10-16 19:18 -0700
  Re: Testing of SR mutual time dilation rotchm <rotchm@gmail.com> - 2015-10-12 08:58 -0700
  Re: Testing of SR mutual time dilation alsor@interia.pl - 2015-10-12 17:22 -0700
  Re: Testing of SR mutual time dilation Julio Di Egidio <julio@diegidio.name> - 2015-10-12 17:56 -0700
    Re: Testing of SR mutual time dilation Julio Di Egidio <julio@diegidio.name> - 2015-10-13 06:28 -0700
    Re: Testing of SR mutual time dilation kenseto <setoken@att.net> - 2015-10-13 08:40 -0700
      Re: Testing of SR mutual time dilation Dirk Van de moortel <dirkvandemoortel@hotspam.not> - 2015-10-14 09:07 +0200
    Re: Testing of SR mutual time dilation John Heath <heathjohn2@gmail.com> - 2015-10-16 19:15 -0700
      Re: Testing of SR mutual time dilation Julio Di Egidio <julio@diegidio.name> - 2015-10-18 09:33 -0700
        Re: Testing of SR mutual time dilation John Heath <heathjohn2@gmail.com> - 2015-10-25 06:07 -0700
          Re: Testing of SR mutual time dilation shuba <tim@sh.uba> - 2015-10-25 19:16 +0000
            Re: Testing of SR mutual time dilation John Heath <heathjohn2@gmail.com> - 2015-10-26 05:09 -0700
              Re: Testing of SR mutual time dilation kefischer <emoneyjoe@iglou.com> - 2015-10-26 08:21 -0400
              Re: Testing of SR mutual time dilation shuba <tim@sh.uba> - 2015-10-26 21:41 +0000
                Re: Testing of SR mutual time dilation John Heath <heathjohn2@gmail.com> - 2015-10-26 19:28 -0700
          Re: Testing of SR mutual time dilation Julio Di Egidio <julio@diegidio.name> - 2015-10-26 08:52 -0700
  Re: Testing of SR mutual time dilation John Gogo <jfgogo22@yahoo.com> - 2015-10-12 20:59 -0700

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