From: ralivingston1952@charter.net   
      
   [[Mod. note -- I have manually rewrapped overly-long lines.  -- jt]]   
      
   On Saturday, March 18, 2017 at 2:23:49 AM UTC-7, Tom Roberts wrote:   
   > ...   
   > Interlude: classical electrodynamics (CE):   
   > In CE one can compute the E and B fields at a a point (x,y,z,t)   
   > in inertial frame S [#] via the Lienard-Wiechert potential. This   
   > evaluates the location and velocity of each charge at a retarded point   
   > (x',y',z',t') [@] such that the interval between these two points isu   
   > null -- i.e. a vacuum light ray would propagate from the primed point   
   > to the unprimed point. E and B are functions of the charge's position   
   > and velocity at the primed point. If you examine the math, you find   
   > that this potential in effect makes a linear extrapolation of each   
   > charge's position to t ("now") in S. As a result, E from a given   
   > charge points very close to where the charge is "now" (in S), and   
   > exactly there if the charge is moving inertially; even though the   
   > EM field propagates at c.   
   >...   
   > Tom Roberts   
      
   This is certainly true for radial motion, but is it true also for   
   tangential motion, which is the relevant case here?  The denominator   
   in the Lienard-Wiechert potentials has a dot product with the radial   
   separation vector.  For a source moving tangential to this vector   
   the denominator is just the radial separation.  It isn't clear to   
   me that this would cause a lateral deviation in the direction of   
   the electrostatic force to where the source "would be" at the present   
   time.  Am I wrong about that?   
      
   Rich L.   
      
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