Coherence Frame, Entanglement Conservation, and Einselection
  In this paper, the theory of coherence frame is developed. Two kinds of coherence frame are classified. Under coherence frame, the entanglement is conserved in the entanglement swapping process, without entanglement sudden death and birth. The einselection method for the preferred basis problem in the entangle process is shown as incomplete. 
Dong-Sheng Wang
quant-ph