Perturbative SO(10) GUT and the minimal Higgs sector

The breaking of SO(10) to SU(3)C×U(1)EMSU(3)C×U(1)EM can be accomplished by just four Higgs fields: the symmetric rank-two tensor, S(54)S(54); a pair of spinors, C(16)C(16) and C¯(16¯); and a vector, T(10)T(10). This setup is also able to generate realistic fermion masses. The heavy color triplets in the vector and spinor fields mediate proton decay via dimension-five operators. The experimental bounds on proton decay constrain the structure and size of the Yukawa operators.