Speaker
Description
We present a Grand Unified Theory where the usual $E_6$ gauge coupling unification is supplemented by a local $SU(2)_F \times U(1)_F$ family symmetry. We discuss its origin inspiring our model by an embedding into $E_8$ which can be seen as an unifying force. We argue that the presence of such a family symmetry has remarkable implications for both high-scale and low scale physics: First, while the usual $27^3$ cubic interactions in the superpotential are forbidden, tree-level Yukawa terms are generated via dimension-four operators upon the breaking of $E_6$ down to its trinification maximal subgroup. Such a breaking will also induce sizable threshold corrections to the gauge couplings at the $E_6$ scale which modifies their running in such a way that it becomes possible to attain a low scale unification picture not far from the reach of a Future $100$ TeV Circular Collider.
On the other hand we demonstrate that the masses of leptons and first generation quarks are of radiative origin whereas second and third quark families are tree-level generated. This results in a CKM-mixing with the Cabibbo where deviations from unitarity are induced via mixing with down-type vector-like quarks as well as radiative corrections.
