Strong WW Scattering at Photon Linear Colliders
  We investigate the possibility of observing strong interactions of longitudinally polarized weak vector bosons in the process $\gamma \gamma \to ZZ$ at a photon linear collider. We make use of polarization of the photon beams and cuts on the decay products of the $Z$ bosons to enhance the signal relative to the background of transversely polarized $ZZ$ pairs. We find that the background overwhelms the signal unless there are strong resonant effects, as for instance from a technicolor analogue of the hadronic $f_2(1270)$ meson. 
M. S. Berger and M. S. Chanowitz