Speaker: Joseph H. Eberly, University of Rochester
Abstract: Surprises have emerged from studies of entanglement evolution in quantum theory, and counter-intuitive predictions  have been confirmed in experiment . It is implicit in most analyses of entanglement evolution that the observer is all-powerful and able to determine a system state completely, but this is usually not true. One reason is that all aspects of a party's quantum state typically cannot be identified. Unknown and non-interacting external parties are typically not mentioned, excluded from view even if entangled with the system of interest. We will refer to this always-present but hidden and non-interacting background universe as the "Moon", and will present a sample sketch showing the effect of this Moon on entanglement evolution.
 See the review: T. Yu and J.H. Eberly, Science 323, 598 (2009).
 M. P. Almeida, F. de Melo, M. Hor-Meyll, A. Salles, S.P. Walborn, P.H. Souto-Ribeiro and L. Davidovich, Science 316, 579 (2007).