In order to clarify both of our understandings and clearly identify any
differences, let us begin by comparing our appreciations of the physics
of this ultra-simple situation: A disc magnet sits at rest on a table,
its static B field is vertical. A copper disc sits at rest on top of
the disc magnet. This is the situation as seen from the LAB frame. In
this LAB frame there is a static B field and no E field. There is no
electric force on the free charges in the copper disc (E=0), and because
the disc is stationary in this frame, there is no QVxB magnetic force on
them. There are thus no currents or separated charges in the stationary
copper disc.
There happens to be a second observer going by on a train moving with a
moderate horizontal velocity V (as measured in the LAB frame). In HIS
frame both the copper disc and the magnet are moving with a common
velocity -V . In HIS frame the free charges in the copper disc are
moving in a magnetic field and must experience the force Q(-V)xB'; where
B'=B. But in HIS frame there is also an electric field: E'=VxB. Thus in
HIS frame the free charges in the copper disc are in equilibrium under
the opposing electric (QE') and magnetic (-QVxB') forces, so that he
also observes no currents or separated charges in the copper disc.
Comments?