SU(5) grand unification on a domain-wall brane from an E-6-invariant action

Abstract

An SU(5) grand unification scheme for effective 3+1-dimensional fields dynamically localized on a domain-wall brane is constructed. This is achieved through the confluence of the clash-of-symmetries mechanism for symmetry breaking through domain-wall formation, and the Dvali-Shifman gauge-boson localization idea. It requires an E6 gauge-invariant action, yielding a domain-wall solution that has E6 broken to differently embedded SO(10) U(1) subgroups in the two bulk regions on opposite sides of the wall. On the wall itself, the unbroken symmetry is the intersection of the two bulk subgroups, and contains SU(5). A 4+1-dimensional fermion family in the 27 of E6 gives rise to localized left-hand..