- #1

- 33

- 0

E.v = 0 and E + v.B = 0

where v is the velocity.

I think this is because g(A,A) = -a squared is invariant. Therefore if a=0, I think this means that A must equal zero in every frame. Is this true, or can A be non zero and we get g(A,A) = 0 (i.e A is null).