Anomalous Higgs interactions in dimensional deconstruction

Abstract

Recent LHC experiments have revealed that Higgs is light. As an interesting candidate to accommodate light Higgs, in this paper we adopt the scenario of dimensional deconstruction, where Higgs is redarded as a pseudo-Nambu-Goldstone boson. Though the scenario is formulated in ordinary 4-dimensional space-time, it may also be interpreted as "latticized" gauge-Higgs unification. We point out that in this scenario Higgs interaction with matter field is anomalous, i.e. its coupling deviates from what the standard model predicts. The interplay between the periodicity of physical observables in the Higgs field and the violation of translational invariance along the extra-space due to the latticization is argued to play an essential role to get the anomalous interaction. Though the predicted anomalous Higgs interaction has much similarity to the one in the gauge-Higgs unification, in the case of dimensional deconstruction the anomaly exists even if we do not introduce bulk mass term for the chiral fermion realized by orbifolding, in clear contrast to the case of gauge-Higgs unification. It in turn means that the anomaly goes away in the continuum limit of the extra-space.

Gauge-Higgs EW and grand unification

“…[29,32] As seen in (18) and (19), all quarks and leptons reside in Ψ 32 , Ψ 11 and Ψ ′ 11 as particles, but not as anti-particles. In other words one can assign the Ψ-fermion number N Ψ such that all quarks and leptons have N Ψ = 1.…”

“…The deviation in the W W Z coupling is less than 0.1%. Three point Higgs couplings are given by [6,16,18] …”

“…In the four-dimensional SO(10) GUT, for instance, quarks and leptons are embedded in Ψ 16L . In the notation in (18), u L is identified with (u c ) L or (u R ) c so that gauge interactions do not conserve quark/lepton number, which induces the proton decay. In the gauge-Higgs grand unification u L and u R , for instance, are embedded as zero modes of 5D fields u and u ′ in Ψ 32 .…”

Gauge-Higgs EW and Grand Unification

“…Gauge-Higgs grand unification provides a new scheme of forbidding the proton decay. [29,32] As seen in (18) and (19), all quarks and leptons reside in Ψ 32 , Ψ 11 and Ψ ′ 11 as particles, but not as anti-particles. In other words one can assign the Ψ-fermion number N Ψ such that all quarks and leptons have N Ψ = 1.…”

Toward realistic gauge–Higgs grand unification

“…In particular, cubic couplings of the Higgs boson with other fields, W , Z, quarks and leptons, are approximately given by the SM couplings multiplied by cos θ H . [7][12]- [15] The corrections to the decay rates H → γγ, Zγ, which take place through one-loop diagrams, turn out finite and small. [11,16] Although infinitely many Kaluza-Klein (KK) excited states of W and top quark contribute, there appears miraculous cancellation among their contributions.…”