Trinification with sin^2\theta_W^0=3/8 and seesaw neutrino mass

Abstract

We realize a supersymmetric trinification model with three families of $({27}_{\mathrm{tri}}+{27}_{\mathrm{tri}}+{\overline{27}}_{\mathrm{tri}})$ by the $Z_3$ orbifold compactification with two Wilson lines. It is possible to break the trinification group to the supersymmetric standard model. This model has several interesting features: the {\it hypercharge quantization}, ${\sin }^2{\theta }_W^0=\frac{3}{8},$ naturally light neutrino masses, and introduction of R-parity. The {\it hypercharge quantization} is realized by the choice of the vacuum, naturally leading toward a supersymmetric standard model.

Comments: 15 pages