Natural unification with a supersymmetricSO(10)GUT×SO(6)Hgauge theory

We propose a unified model of elementary particles based on a supersymmetric $\mathrm{SO}{\mathrm{}\left(10\right)\mathrm{}}_{\mathrm{GUT}}\times \mathrm{SO}{\mathrm{}\left(6\right)\mathrm{}}_H$ gauge theory. This model completely achieves natural unification of the strong and electroweak interactions without any fine tunings. The masslessness of Higgs doublets is guaranteed by a chiral $\mathrm{U}{\mathrm{}\left(1\right)\mathrm{}}_A$ symmetry. On the other hand, the Higgs triplets have a GUT-scale mass invariant under the chiral $\mathrm{U}{\mathrm{}\left(1\right)\mathrm{}}_A$.