Generic Emergence of Objectivity of Observables in Infinite Dimensions
A recent paper co-authored by Dr Marco Piani (CNQO, Department of Physics, University of Strathclyde) is the cover article of Physical Review Letters (Vol 121, issue 16, 19 October 2018). The research tackles one of the deepest questions of quantum theory, how does the ordinary world we see arise from a fundamentally quantum reality. The approach considered is called Quantum Darwinism by which properties of a quantum system (momentum, energy etc.) become "real" due to multiple observers probing different fractions of the environment. Previously this mechanism was shown to work for small quantum systems, this work extends this to infinite dimensional systems.
In quantum Darwinism, information about a system (brown cat in the middle) becomes classical and objective when multiple observers (painters) indirectly probe the quantum state of the system (bottom) by accessing different parts of its environment. (Artwork by Joseph Hollis)
 Generic Emergence of Objectivity of Observables in Infinite Dimensions, Paul A. Knott, Tommaso Tufarelli, Marco Piani, and Gerardo Adesso, Phys. Rev. Lett. 121, 160401 (2018) https://doi.org/10.1103/PhysRevLett.121.160401