Re: teeny atoms absorb huge EM waves

[Leigh Palmer <palmer@SFU.CA>]

At 21:18 -0700 8/2/99, William Beaty wrote:

> ...
> In EM, I imagine that the KE of a moving charge is almost entirely stored
> as a magnetic field, and the PE of an assemblage of charges is almost
> entirely stored as an electric field.
>
> ...
>
> All of the above is not necessarily a rigid worldview which I will defend
> beyond the bounds of reason.  I state it here so people can take pokes at
> it.  Gimme your best shot!  :)

OK, Bill. I'll accept that challenge. Suppose I think of the potential
energy of an assemblage of charges as being associated entirely with
their geometrical relationships. I can calculate that energy entirely
in terms of their geometry, and Then I may think of the energy of that
system as being localized in the charges, or at least as being inside
the smallest convex polyhedron I can draw around them. You, on the
other hand, think of that energy as being distributed in space; and
potentially in all of space!

If we can't agree on where this stuff called energy is, how can we
possibly ascribe reality to it?

In the final analysis the thing we call energy is a useful abstract
construct which, it turns out, can be looked at in more than one way.
EM waves do, indeed, propagate, but energy does not! EM waves are not
"pure energy". EM waves are a useful construct for describing a real
system. Physics is the activity of making descriptions of the real
world. Reification is a sin.

I will close by merely mentioning the authors of my standard gospels
on this topic, Bill Burke and Richard Feynman. I've cited them so
many times that I won't waste any more of your valuble disk space.

Leigh