From classical chaos to decoherence in Robertson-Walker cosmology
  We analyse the relationship between classical chaos and particle creation in Robertson-Walker cosmological models with gravity coupled to a scalar field. Within our class of models chaos and particle production are seen to arise in the same cases. Particle production is viewed as the seed of decoherence, which both enables the quantum to classical transition, and ensures that the correspondence between the quantum and classically chaotic models will be valid 
Fernando C. Lombardo, Mario Castagnino, and Luca Bombelli