Electroweak unification into a five-dimensional SU(3) at a TeV

We apply a recently proposed mechanism for predicting the weak mixing angle to theories with TeV-size dimensions. "Reconstruction" of the associated moose (or quiver) leads to theories which unify the electroweak forces into a five-dimensional SU(3) symmetry. Quarks live at an orbifold fixed point where SU(3) breaks to the electroweak group. A variety of theories - all sharing the same successful prediction of sin²θ_W - emerges; they differ primarily by the spatial location of the leptons and the absence or presence of supersymmetry. A particularly interesting theory puts leptons in a Konopinski-Mahmoud triplet and suppresses proton decay by placing quarks and leptons on opposite fixed points.