This model yields a prediction for proton decay. However, the experiments thus far have not observed proton decay, and the resulting lower limit for the halflife of the proton not contradicts the predictions of this model. However, the elegance of the model has led particle physicists to use it as the foundation for more complex models which yield longer proton lifetimes.

There is also an adjoint scalar field, a 24 called the Higgs field which acquires a VEV proportional to . This results in a spontaneous symmetry breaking from SU(5) to and also, , , , . Of course, calling the representations things like and 24 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 theory was invented by Howard Georgi and Sheldon Glashow.