Exceptional coset spaces and unification in six dimensions

The coset spaces E8/SO(10)×HF allow complex structures which can account for three quark–lepton generations including right-handed neutrinos. We show that in the context of supersymmetric SO(10) gauge theories in 6 dimensions they also provide the Higgs fields which are needed to break the electroweak and B−L gauge symmetries, and to generate small neutrino masses via the seesaw mechanism.