Gribov ambiguity and degenerate systems
  The relation between Gribov ambiguity and degeneracies in the symplectic structure of physical systems is analyzed. It is shown that, in finite-dimensional systems, the presence of Gribov ambiguities in regular constrained systems (those where the constraints are functionally independent) always leads to a degenerate symplectic structure upon Dirac reduction. The implications for the Gribov-Zwanziger approach to QCD are discussed. 
Fabrizio Canfora, Fiorenza de Micheli, Patricio Salgado-Rebolledo,   Jorge Zanelli
hep-th