A large class of models addressing the electroweak naturalness problem
postulates the existence of new spontaneously broken global symmetries above
the weak scale. The Higgs boson arises as a pseudo-Nambu-Goldstone boson (pNGB)
whose interactions are nonlinear due to the presence of de- generate vacua. We
argue that, once the normalization of the pNGB decay constant f is determined,
the Higgs nonlinear interactions in the gauge sector are universal in the
infrared and independent of the symmetry breaking pattern G/H, even after
integrating out heavy composite resonances. We propose a set of "universal
relations" in Higgs couplings with electroweak gauge bosons and in triple gauge
boson couplings, which are unique predictions of the universal nonlinearity.
Experimental measurements of these relations would serve as the litmus test of
a pNGB Higgs boson.Comment: 5 page