| | 12 | The discussed model utilizes four-fermion interactions in its Lagrangian to characterize interactions among Standard Model (SM) elementary fermions at the ultraviolet (UV) cutoff. These interactions, following the Nambu–Jona-Lasinio (NJL) or Einstein-Cartan type, effectively represent more fundamental interactions in the UV completion. The incorporation of effective four-fermion interactions stems from a theoretical inconsistency observed between the bilinear Lagrangian of the SM chiral (parity-violating) gauged fermions and the UV regularization of unidentified dynamics. This inconsistency hints at the presence of four-fermion interactions at the UV cutoff. [[BR]] The model is grounded in a strong four-fermion coupling UV fixed point at TeV scales, giving rise to massive composite particles as bound states of SM fermions. Bound states are classified into bosons and fermions, with bosons engaging in interactions with lepton-quark and quark-quark pairs. Fermions consist of either 3 quarks, leptons, or mixed combinations. The SM chiral gauge symmetries remain intact, and composite particles interact with SM gauge bosons. As the energy scale decreases and composite particles disintegrate, the model undergoes a first-order phase transition involving the breaking of SM chiral gauge symmetries. It transitions to a weak four-fermion coupling infrared (IR) fixed point at the electroweak scale, where the low-energy SM is realized. The energetically favorable symmetry-breaking ground state leads to the generation of the top quark mass through spontaneous symmetry breaking, and the masses of other fermions follow a hierarchy via explicit symmetry breaking through family mixing. |
