Decoherence and the Branching of Chaos-less Classical Trajectory
  This study was started to know mysterious classicality of nuclei.   This time, I found a new rule for decoherence. I used a model without chaos. As a result, it was shown that not only the intersection of classical trajectories but also branching of classical trajectories are needed for decoherence. In other words, it was shown that interactions between a main system and environments have to make enough branchings of classical trajectories of the main system for decoherence. 
Takuji Ishikawa
quant-ph nucl-th