  The Higgs boson is unified with gauge fields in the gauge-Higgs unification.
The $SO(5) \times U(1)$ gauge-Higgs electroweak unification in the
Randall-Sundrum warped space yields almost the same phenomenology at low
energies as the standard model, and gives many predictions for the Higgs
couplings and new $W', Z'$ bosons around $6 \sim 8$ TeV, which can be tested at
14 TeV LHC. The gauge-Higgs grand unification is achieved in $SO(11)$ gauge
theory. It suggests the existence of the sixth dimension (GUT dimension) in
addition to the fifth dimension (electroweak dimension). The proton decay is
naturally suppressed in the gauge-Higgs grand unification.
