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DOE OSTI · 2470521

Pointer States and Quantum Darwinism with Two-Body Interactions

Duruisseau, Paul·Touil, Akram·Deffner, Sebastian
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Abstract

Quantum Darwinism explains the emergence of classical objectivity within a quantum universe. However, to date, most research on quantum Darwinism has focused on specific models and their stationary properties. To further our understanding of the quantum-to-classical transition, it appears desirable to identify the general criteria a Hamiltonian has to fulfill to support classical reality. To this end, we categorize all N-qubit models with two-body interactions, and show that only those with separable interaction of the system and environment can support a pointer basis. We further demonstrate that “perfect” quantum Darwinism can only emerge if there are no intra-environmental interactions. Our analysis is complemented by solving the ensuing dynamics. We find that in systems exhibiting information scrambling, the dynamical emergence of classical objectivity directly competes with the non-local spread of quantum correlations. Our rigorous findings are illustrated through the numerical analysis of four representative models.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSdecoherencequantum Darwinism

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Duruisseau, Paul, Touil, Akram, Deffner, Sebastian. 2023-11-22. Pointer States and Quantum Darwinism with Two-Body Interactions. https://doi.org/10.3390/e25121573

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