Re: EM field question

On Sat, 21 Oct 2006, main_engineering wrote:

Given any 2 arbitrary 4-current densities and their resulting EM fields.

J1_u, is located at coordinates (x1,t1), and radiates an EM field F1^uv
J2_u, is located at coordinates (x2,t2), and radiates an EM field F2^uv
Where x2,t2 and x1,t1, are two different but nearby points in space-time.

Are there any solutions to the following Lorentz force density equation?

(J1_uF2^uv) =/= (J2_uF1^uv)

How do I prove it one way or the other?

Trivially, one has the case when J2 is located in one of the minimum of 2
required null directions where J1 cannot radiate power, but J2 does
radiate in the direction of J1.

"Nearby" is irrelevant, J1 located _at_ (x1,t1) is a classical
impossibility. J1 in the neighbourhood of (x1,t1) is possible, but no
classical finite current density at a _single_ point will give you any
radiated power.

--
Timo Nieminen - Home page: http://www.physics.uq.edu.au/people/nieminen/
E-prints: http://eprint.uq.edu.au/view/person/Nieminen,_Timo_A..html
Shrine to Spirits: http://www.users.bigpond.com/timo_nieminen/spirits.html

.