QCD vacuum as a chromomagnetic superconductor: Microscopic physics

The compactness of the QCD gauge group leads to the existence of chromomagnetic monopole configurations. The interactions of these monopoles are studied using electric-magnetic duality as a guide. It is shown that the gluon-monopole interaction acquires an extra minus sign which tends to destabilize the monopole configurations. A model is presented which exploits this observation. We present a scenario where the monopoles condense, giving chromomagnetic superconductivity, via a first-order phase transition at a scale where the electric and magnetic charges are equal, i.e., α=1/2. In this vacuum medium gluons propagate like 1/$k^4$ which is now seen to be the dual equivalent of the statement that the vacuum is a chromomagnetic superconductor.