Confining dyon gas with finite-volume effects under control
  As an approach to describe the long-range properties of non-Abelian gauge theories at non-zero temperature T < T_c, we consider a non-interacting ensemble of dyons (magnetic monopoles) with non-trivial holonomy. We show analytically, that the quark-antiquark free energy from the Polyakov loop correlator grows linearly with the distance, and how the string tension scales with the dyon density. In numerical treatments, the long-range tails of the dyon fields cause severe finite-volume effects. Therefore, we demonstrate the application of Ewald's summation method to this system. Finite-volume effects are shown to be under control, which is a crucial requirement for numerical studies of interacting dyon ensembles. 
Falk Bruckmann, Simon Dinter, Ernst-Michael Ilgenfritz, Benjamin   Maier, Michael Muller-Preussker, Marc Wagner
hep-ph hep-lat hep-th