Covariant Mixmaster Dynamics
  We provide a Hamiltonian analysis of the Mixmaster Universe dynamics on the base of a standard Arnowitt-Deser-Misner Hamiltonian approach, showing the covariant nature of its chaotic behaviour with respect to the choice of any time variable, from the point of view either of the dynamical systems theory, either of the statistical mechanics one. 
Giovanni Imponente and Giovanni Montani