Gauge-Higgs unification, topology and hierarchical fermion masses

by C.S. Lim (Tokyo Woman's Christian U.)

Friday 22 Mar 2019, 14:30 → 15:30 Europe/Berlin

SR2 (Bldg. 2A)

Gauge-Higgs unification (GHU) is one of BSM scenarios, where the Higgs field is originally (higher dimensional) gauge field and the well-known hierarchy problem is solved by virtue of the gauge symmetry. In GHU, the topological nature of the extra dimension plays a crucial role, i.e. the Higgs field may be regarded as a sort of AB (or Wilson-loop) phase. In this talk I focus on another problem in the Higgs sector of the SM: fermion masses cannot be predicted. I discuss an interesting possibility that the impressive property of the observed hierarchical fermion masses is naturally understood in the framework of GHU again due to the topological nature of extra dimension. Namely, I propose a scenario where such hierarchical structure of fermion masses is attributed to the presence of topological soliton, i.e. a magnetic monopole placed inside the extra space. The most recent related work will be also mentioned about very briefly.