title: Universal irreversibility of normal quantum diffusion.
abstract: Time-reversibility measured by the deviation of perturbed time-reversed motion from the unperturbed motion is examined for normal quantum diffusion exhibited by four classes of quantum maps with contrasting physical nature. Irrespective of the system, there exists a universal minimal quantum threshold above which the system completely loses memory of the past. The time-reversed dynamics as well as the time-reversal characteristics are asymptotically universal curves independent of the details of the systems.
authors.affiliation: Yamada Physics Research Laboratory, Aoyama 5-7-14-205, Niigata 950-2002, Japan.
authors.forename: Hiroaki S
authors.initials: HS
authors.lastname: Yamada
authors.forename: Kensuke S
authors.initials: KS
authors.lastname: Ikeda