Re: Curvature of Space

[Leigh Palmer <palmer@sfu.ca>]

> Scattering of light by a strong electric field is called Delbrueck
> scattering.  It is observable when a photon scatters from the field
> of an atomic nucleus.  See Jauch and Rohrlich, "The Theory of Photons
> and Electrons", section 15-8.  In terms of Feynman diagrams, the
> incoming photon splits into an electron-positron pair, which must
> interact with the static field not once but twice (or more), then
> recombine to form the outgoing photon.  What we call a "photon", you
> see, is really a seething bundle of virtual particles, including
> electron-positron pairs that can be deflected by an electromagnetic
> field.

Yes, but single photons refrain from doing so for reasons of
discretion and simultaneous energy and momentum conservation *in
free space*. Delbr=FCck scattering requires an interlocutory atom
to mediate the momentum problem.

I took the original question to refer to the deflection of a
photon in an electric field. Nothing was said about the presence
of another object; if that is allowed why not just add a
gravitational field; that works - or perhaps a Venetian blind.

How come no one attacks my symmetry argument for nondeflection?
I thought it was pretty cute; I'd like to know if it has any
holes in it.

Leigh