Poincaré recurrence theorem in scattering state

According to https://en.wikipedia.org/wiki/Poincar%C3%A9_recurrence_theorem#Quantum_mechanical_version the most recent paper is Schulman, L. S. (1978). "Note on the quantum recurrence theorem". Phys. Rev. A 18 (5): 2379–2380.

which assumes only discrete energy levels.

If there is scattering state, the energy level is typically continuous. My question is, in such system, does the Poincaré recurrence theorem still hold? Why?

• The Poincare recurrence theorem does not hold for unbound systems. In bound systems it's pretty much useless, I would say. Far more important would be ergodicity and results like the KAM-theorem. – CuriousOne Aug 2 '16 at 6:00
• – Count Iblis Aug 2 '16 at 6:23