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)×U(1) gauge-Higgs unification model are determined. The result is summarized in the effective interactions for θˆH(x)=θH+H(x)/fH where θH is the Wilson line phase and H(x) is the 4D Higgs field. The Yukawa, WWH and ZZH couplings vanish at θH=12π. There emerges the possibility that the Higgs particle becomes stable.