From: tjroberts137@sbcglobal.net   
      
   On 11/6/19 3:13 PM, richalivingston@gmail.com wrote:   
   > Consider viewing the satellites from the north pole, with all the   
   > satellites in an equatorial orbit.  If all the satellites are at the   
   > same altitude the (GR) gravitational red shift will be equal for all of   
   > them.  They are all moving at the same speed in this orbit, so the SR   
   > time dilation will also be the same.  You could synchronize the clocks   
   > with a single pulse from the north pole.  The orbiting clocks are now   
   > synchronized and running at the same speed.   
      
   Whenever you say "synchronized" you must also say in which frame it   
   applies (not doing that is what confused PK). This synchronization is in   
   the frame of the north pole. The clocks are "running at the same speed"   
   when measured in the frame of the north pole.   
      
   That is close to what the GPS does. GPS clocks are synchronized in the   
   ECI frame, not the instantaneously co-moving inertial frame of any   
   satellite.   
      
   > [to PK] Doesn't that counter your argument?   
      
   Since synchronization is frame dependent, no. But the frame-jumping he   
   performs does invalidate his argument.   
      
   Tom Roberts   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)