If it is assumed that the neutrinos interact with the Higgs field with approximately the same strengths as the charged fermions do, the heavy mass should be close to the GUT scale. Because the Standard Model has only one fundamental mass scale,The Standard Model fundamental mass scale can be taken as the scale of breaking. all particle massesThe mass of the electron and the mass of the Z boson are examples of particle masses set by the Standard Model fundamental mass scale. must arise in relation to this scale.
