The mixmaster universe is chaotic
  For the past decade there has been a considerable debate about the existence of chaos in the mixmaster cosmological model. The debate has been hampered by the coordinate, or observer dependence of standard chaotic indicators such as Lyapanov exponents. Here we use coordinate independent, fractal methods to show the mixmaster universe is indeed chaotic. 
Neil J. Cornish (Cambridge Uni.), Janna J. Levin (UC, Berkeley)