Wigner function probe of quantum chaos in complex collisions
We study Schrödinger cat states in bimolecular chemical reactions. The time for disappearance of the interference fringes is estimated from heuristic arguments related to fingerprints of chaotic dynamics of a classical counterpart of the rotating complex. Validity of this estimate is confirmed by the analysis of the Wigner function for a number of bimolecular reactions. Thus we demonstrate the quantum-classical transition in temporal behavior of highly excited quantum many-body systems in the absence of external noise and coupling to an environment.