Effective potential and universality in GUT-inspired gauge-Higgs unification

The effective potential for the Aharonov-Bohm phase ₇ in the fifth dimension in GUT-inspired SO (5) (1) (3) gauge-Higgs unification is evaluated to show that dynamical electroweak symmetry breaking takes place with ₇0, where the four-dimensional Higgs boson mass of 125 GeV is generated at the quantum level. The cubic and quartic self-couplings (₃, ₄) of the Higgs boson are found to satisfy universal relations, i. e. , they are determined, to high accuracy, solely by ₇, irrespective of the values of other parameters in the model. For ₇=0. 1 (0. 15), ₃ and ₄ are smaller than those in the standard model by 7. 7% (8. 1%) and 30% (32%), respectively.