The Pati-Salam model is a GUT theory which states that the gauge group is either Special unitary group or Special unitary group and the fermions form three families, each consisting of the representations Representations of Lie groups/algebras and Representations of Lie groups/algebras. This includes the right handed neutrino, which is now known to exist. See neutrino oscillations. There is also a (4,1,2) and/or a scalar field called the Higgs field which acquires a VEV. This results in a spontaneous symmetry breaking from to or from to and also, , , , and . Of course, calling the representations things like and (6,1,1) is purely a physicist's convention, not a mathematician's convention, where representations are either labelled by Young tableaux or Dynkin diagrams with numbers on their vertices, but still, it is standard among GUT theorists.

Since the homotopy group , this model predicts monopoles. See 't Hooft-Polyakov monopole.

This model was invented by Jogesh Pati and Abdus Salam.