Objective past of a quantum universe: Redundant records of consistent histories

Journal Article · Mon Mar 21 00:00:00 EDT 2016 · Physical Review A

DOI:https://doi.org/10.1103/PhysRevA.93.032126· OSTI ID:1296658

Reidel, C. Jess ^[1]; Zurek, Wojciech H. ^[2]; Zwolak, Michael ^[3]

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1. Perimeter Institute for Theoretical Physics, Waterloo, ON (Canada); IBM Watson Research Center, Yorktown Heights, NY (United States); Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
3. Oregon State Univ., Corvallis, OR (United States)

Motivated by the advances of quantum Darwinism and recognizing the role played by redundancy in identifying the small subset of quantum states with resilience characteristic of objective classical reality, we explore the implications of redundant records for consistent histories. The consistent histories formalism is a tool for describing sequences of events taking place in an evolving closed quantum system. A set of histories is consistent when one can reason about them using Boolean logic, i.e., when probabilities of sequences of events that define histories are additive. However, the vast majority of the sets of histories that are merely consistent are flagrantly nonclassical in other respects. This embarras de richesses (known as the set selection problem) suggests that one must go beyond consistency to identify how the classical past arises in our quantum universe. The key intuition we follow is that the records of events that define the familiar objective past are inscribed in many distinct systems, e.g., subsystems of the environment, and are accessible locally in space and time to observers. We identify histories that are not just consistent but redundantly consistent using the partial-trace condition introduced by Finkelstein as a bridge between histories and decoherence. The existence of redundant records is a sufficient condition for redundant consistency. It selects, from the multitude of the alternative sets of consistent histories, a small subset endowed with redundant records characteristic of the objective classical past. Furthermore, the information about an objective history of the past is then simultaneously within reach of many, who can independently reconstruct it and arrive at compatible conclusions in the present.

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
• Sponsoring Organization: USDOE Laboratory Directed Research and Development (LDRD) Program
• Grant/Contract Number: AC52-06NA25396
• OSTI ID: 1296658
• Alternate ID(s): OSTI ID: 1242843
• Report Number(s): LA-UR-13-29441
• Journal Information: Physical Review A, Vol. 93, Issue 3; ISSN 2469-9926
• Publisher: American Physical Society (APS)
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
atomic and nuclear physics