Vector-boson versus gluon fusion at hadron colliders

We use chiral perturbation theory to show that pseudo-Goldstone boson scattering and gluon fusion probe different aspects of electroweak symmetry breaking at hadron colliders. In particular, different physics may be responsible for unitarizing the lowest-order pseudo-Goldstone boson scattering amplitudes and the gluon fusion process. We first show this within the context of strict chiral perturbation theory, and then discuss it using the language of resonances.