I once found an old book on Maxwell's equations, I think the date was 1907, and I noticed that it assumed that electric and magnetic fields had instantaneous effect. That made the math simpler but it bothered me.

So when I read your explanation, it made sense that old physicists would assume that moving charges would have exactly the stationary charge, plus an extra magnetic charge.

But if it takes time for an electric field to move, then wouldn't moving charges have their fields be at an angle? One charge experiences the field from where the other one was in the past -- the field would be tilted.

If that happened at just the right amount, the reduction in the "stationary" perpendicular force would exactly balance the new magnetic force, and both the stationary and the moving force calculations would give the same answer.

Could something like that happen?

]]>Which is why I'm so freaking *jealous* right now.