Spontaneous topological transitions of electromagnetic fields in   spatially inhomogeneous CP-odd domains
  Metastable CP-odd domains of the hot QCD matter are coupled to QED via the chiral anomaly. The topology of electromagnetic field in these domains is characterized by magnetic helicity. It is argued, using the Maxwell-Chern-Simons model, that spatial inhomogeneity of the domains induces spontaneous transitions of electromagnetic field between the opposite magnetic helicity states. 
Kirill Tuchin
hep-ph