The end of the p-form hierarchy

Understand

The introduction of a non-abelian gauge group embedded into the rigid symmetry group G of a field theory with abelian vector fields and no corresponding charges, requires in general the presence of a hierarchy of p-form gauge fields.

• The full gauge algebra of this hierarchy can be defined independently of a specific theory and is encoded in the embedding tensor that determines the gauge group.
• When applied to specific Lagrangians, the algebra is deformed in an intricate way and in general will only close up to equations of motion.
• The group-theoretical structure of the hierarchy exhibits many interesting features, which have been studied starting from the low-p forms.