2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/193203The breaking of SO(10) to SU(3)_C x U(1)_EM can be accomplished by just four Higgs fields: the symmetric rank-two tensor, S(54); a pair of spinors, C(16) and Cbar(16bar); and a vector, 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.v2: discussion about gauge coupling unification extended; figure added; to appear in Phys. Lett. BHigh Energy Physics - Phenomenologytext