Yukawa Couplings and Effective Interactions in Gauge-Higgs Unification
  The wave functions and Yukawa couplings of the top and bottom quarks in the SO(5) x U(1) gauge-Higgs unification model are determined. The result is summarized in the effective interactions for \hat \theta_H(x) = \theta_H + H(x)/f_H where \theta_H is the Wilson line phase and H(x) is the 4D Higgs field. The Yukawa, WWH and ZZH couplings vanish at \theta_H = \onehalf \pi. There emerges the possibility that the Higgs particle becomes stable. 
Yutaka Hosotani and Yoshikazu Kobayashi