Re: Curvature of Space

[Leigh Palmer <palmer@sfu.ca>]

> A static field is not free space.  It assumes a fixed source,
> that is, an object that can absorb an arbitrary amount of momentum.

A static field *embedded in* free space is what I believe is meant.
The field source can only absorb linear momentum if a force acts on
it, and for that to happen ther has to be a field mechanism. Charge
would do, of course, but photons are uncharged.

> I'm sorry, I already deleted your symmetry argument.  But I believe
> that for Delbrueck scattering to work, you need an inhomogeneous
> field.  Does that help?

The symmetry argument is simple: If there is a force acting on the
photon due to an electric field, what is its direction? Let me
point out in advance that a cross product does not have an
intrinsic direction. That should save some time.

If no direction can be determined then the deflection is nil.

Leigh