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arXiv · 0704.3615

Quantum Darwinism in quantum Brownian motion: the vacuum as a witness

Robin Blume-Kohout·Wojciech H. Zurek
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Abstract

We study quantum Darwinism -- the redundant recording of information about a decohering system by its environment -- in zero-temperature quantum Brownian motion. An initially nonlocal quantum state leaves a record whose redundancy increases rapidly with its spatial extent. Significant delocalization (e.g., a Schroedinger's Cat state) causes high redundancy: many observers can measure the system's position without perturbing it. This explains the objective (i.e. classical) existence of einselected, decoherence-resistant pointer states of macroscopic objects.

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Robin Blume-Kohout, Wojciech H. Zurek. 2007-04-26. Quantum Darwinism in quantum Brownian motion: the vacuum as a witness. https://doi.org/10.1103/physrevlett.101.240405

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