Sunday, August 3, 2008

How Does Light Propagate?

In the 19th century a number of physicists worked hard to understand the mechanism of the propagation of electromagnetic radiation. They failed utterly. I claim that the physicists of the 20th century did no better. I am allowed to speculate on this mechanism. I said earlier that to ignore the underlying electric fields of charged particles and to focus only on the net fields is an error, an error that goes back to Michael Faraday and James Clerk Maxwell among others.

We start with the choice that the electric fields of charged particles are real, are of infinite extent, and overlay each other everywhere. Already we almost have a medium. In the case when one charged particle moves with respect to the others (a rather artificial special case), necessarily its electric field must move with it. I claim that it does not move instantaneously. Rather, the adjustment of the electric field takes place in a measured fashion as it moves with respect to the others. With each increment of motion of the particle, the adjustment of the electric field is "telegraphed" outward from the particle at a characteristic speed, known to us as the speed of light. Why? To put it in homey language, the electric field of a charged particle "knows" it wants to be symmetrically disposed about the particle, and in moving over it encounters a miniscule bit of "resistance" as it slides through the overlaid electric fields of all the other particles. Hence, there's a bit of delay as the adjustment takes place. That's the medium for you. There's no elastic solid-like monolithic aether. There's no sea of ultra-mundane particles zipping around. The medium consists only of what we always knew was there if we had only chosen to look at it clearly. Of course, there's plenty of details to figure out. And of course, we don't know exactly what these electric fields are, nor do we know exactly how they work, but its a start.

2 comments:

T. Whitman said...

Any luck with an answer for this? If light is a wave, shouldn't it need to propagate through something? Vacuum almost makes no sense, as a wave couldn't propagate through absolute nothing. No formal physics background here aside from phys 1 and 2 in college, just very curious on the subject

Lee Shimmin said...

I certainly agree that 'vacuum' makes no sense. The older definition of a wave was "a disturbance propagating through a medium." I'm saying that the medium is the underlying electric fields of all the charged particles in the universe. Every charged particle has an electric field of infinite extent. "Normal" physics is not concerned with these underlying electric fields; it only deals with the 'net' fields.