SU(2) vacuum dynamics in applied external magnetic field
  The vacuum dynamics of SU(2) lattice gauge theory is studied by means of a gauge-invariant effective action, both at zero and finite temperature. Working with lattices up to 32^4 we check the scaling of the energy density with the magnetic length. We find that the screening at zero temperature of the applied external magnetic field weakens by increasing the temperature. 
Paolo Cea and Leonardo Cosmai