Energy-momentum tensors in gauge theory
  In field theory on a fibre bundle Y->X, an energy-momentum current is associated to a lift onto Y of a vector field on X. Such a lift by no means is unique, and contains a vertical part. It follows that: (i) there are a set of different energy-momentum currents, (ii) the Noether part of an energy-momentum current can not be taken away, (iii) if a Lagrangian is not gauge-invariant, the energy-momentum fails to be conserved. 
G.Sardanashvily