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Weinberg-Witten Theorem to the possibility of quantum gravity?

(Described here: http://en.wikipedia.org/wiki/Weinberg-Witten_theorem)

From the Wikipedia article, the conclusion is

I don't understand how that can be correct. Deser and Feynmann...massless

particles (either composite or elementary) with spin j > 1/2 cannot

carry a Lorentz-covariant current, while massless particles with spin j

> 1 cannot carry a Lorentz-covariant stress-energy.

(independently?) showed that General Relativity can be understood (at

least in asymptotically flat spacetimes) as the field theory of a spin-2

massless particle whose source is the total stress-energy tensor. I know

that this approach is not renormalizable, at least not in any obvious

way, but it seems to conflict with the Weinberg-Witten Theorem. Is the

WWT in some way a

*proof*that the Deser/Feynmann theory is not

renormalizable?

One thing that is a little confusing about the Deser/Feynmann theory is

exactly what the stress-energy tensor is. The assumption is that the

spin-two particle couples to the total stress-energy, including the

stress-energy of the particle itself. This is apparently very different

from GR, in which the appropriate stress-energy tensor has no

contribution due to gravity. I don't have a good grasp of how this is

reconciled.