In a theory intended to represent a physical interaction where the coupling constant is known to be non-zero, Landau poles or triviality may be viewed as a "sign of incompleteness in the theory". For example, QED is usually not believed to be a complete theory on its own, because it does not describe other fundamental interactions, and contains a Landau pole. Conventionally QED forms part of the more fundamental electroweak theory. The group of electroweak theory also has a Landau pole which is usually considered to be a signal of a need for an ultimate embedding into a Grand Unified Theory. The grand unified scale would provide a natural cutoff well below the Landau scale, preventing the pole from having observable physical consequences.