Symmetry breaking induced by 't Hooft non-abelian flux
  We analyze a SU(N) gauge theory on $\mathcal{M}_4 \times T^2$. We find and catalogue all possible degenerate zero-energy stable configurations in the case of trivial or non-trivial 't Hooft non abelian flux. We describe the residual symmetries of each vacua and the 4-dimensional effective spectrum in terms of continous and discrete parameters, respectively. 
M. Salvatori