2007/11/30 by M. Maniatis, A. von Manteuffel, O. Nachtmann · 3 citations
Computer Science · Physics and Astronomy · #Computational Physics and Python Applications #Degenerate energy levels #Electroweak interaction #Fermion #Higgs boson #Homogeneous space #Massless particle #Neutrino Physics Research #Particle physics theoretical and experimental studies #Scalar (mathematics) #Symmetry breaking #Yukawa potential #hep-ph
paper · pdf · doi:10.1140/epjc/s10052-008-0726-z
published as Eur.Phys.J.C57:739-762,2008 · 24 pages. Version published in EPJC. Minor changes as suggested by the referee
openalex publication_date 2008/10/01 · arxiv created 2008/10/27 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We study a two-Higgs-doublet model with four generalised CP symmetries in the scalar sector. Electroweak symmetry breaking leads automatically to spontaneous breaking of two of them. We require that these four CP symmetries can be extended from the scalar sector to the full Lagrangian and call this requirement the principle of maximal CP invariance. The Yukawa interactions of the fermions are severely restricted by this requirement. In particular, a single fermion family cannot be coupled to the Higgs fields. For two fermion families, however, this is possible. Enforcing the absence of flavour-changing neutral currents, we find degenerate masses in both families or one family massless and one massive. In the latter case the Lagrangian is highly symmetric, with the mass hierarchy being generated by electroweak symmetry breaking. Adding a third family uncoupled to the Higgs fields and thus keeping it massless we get a model which gives a rough approximation of some features of the fermions observed in Nature. We discuss a number of predictions of the model which may be checked in future experiments at the LHC.