# Quantum Darwinism

## Abstract

Quantum Darwinism describes the proliferation, in the environment, of multiple records of selected states of a quantum system. It explains how the quantum fragility of a state of a single quantum system can lead to the classical robustness of states in their correlated multitude; shows how effective ‘wave-packet collapse’ arises as a result of the proliferation throughout the environment of imprints of the state of the system; and provides a framework for the derivation of Born’s rule, which relates the probabilities of detecting states to their amplitudes. Taken together, these three advances mark considerable progress towards settling the quantum measurement problem.

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## Acknowledgements

I am grateful to R. Blume-Kohout, F. Cucchietti, J. P. Paz, D. Poulin, H.-T. Quan and M. Zwolak for stimulating discussions. This research was supported by DoE through an LDRD grant at Los Alamos, and, in part, by the Foundational Questions Institute (FQXi).

## Author information

Correspondence to Wojciech Hubert Zurek.

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• #### DOI

https://doi.org/10.1038/nphys1202

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