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Title: Complementarity of quantum discord and classically accessible information

The sum of the Holevo quantity (that bounds the capacity of quantum channels to transmit classical information about an observable) and the quantum discord (a measure of the quantumness of correlations of that observable) yields an observable-independent total given by the quantum mutual information. This split naturally delineates information about quantum systems accessible to observers – information that is redundantly transmitted by the environment – while showing that it is maximized for the quasi-classical pointer observable. Other observables are accessible only via correlations with the pointer observable. In addition, we prove an anti-symmetry property relating accessible information and discord. It shows that information becomes objective – accessible to many observers – only as quantum information is relegated to correlations with the global environment, and, therefore, locally inaccessible. Lastly, the resulting complementarity explains why, in a quantum Universe, we perceive objective classical reality while flagrantly quantum superpositions are out of reach.
 [1] ;  [2]
  1. Oregon State Univ., Corvallis, OR (United States). Department of Physics
  2. Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Divison; Santa Fe Inst. (SFI), Santa Fe, NM (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 2045-2322
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Scientific Reports
Additional Journal Information:
Journal Volume: 3; Journal ID: ISSN 2045-2322
Nature Publishing Group
Research Org:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org:
Country of Publication:
United States
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; information theory and computation; quantum information; quantum mechanics; theoretical physics
OSTI Identifier: