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# Dynamics of quantum information

## Abstract

The ability to harness the dynamics of quantum information and entanglement is necessary for the development of quantum technologies and the study of complex quantum systems. On the theoretical side, the dynamics of quantum information is a topic that is helping us to unify and confront common problems in otherwise disparate fields in physics, such as quantum statistical mechanics and cosmology. On the experimental side, impressive developments in the manipulation of neutral atoms and trapped ions are providing new ways to probe their quantum dynamics. Here, we overview and discuss progress in characterizing and understanding the dynamics of quantum entanglement and information scrambling in quantum many-body systems. The level of control attainable over both the internal and external degrees of freedom of individual particles in these systems provides insight into the intrinsic connection between entanglement and thermodynamics, and between bounds on information transport and computational complexity of interacting systems. In turn, this understanding should enable the realization of quantum technologies.

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## Acknowledgements

The authors thank M. Norcia and A. Shankar for their reading of the manuscript and feedback. This work is supported by the US Air Force Office of Scientific Research grant FA9550-18-1-0319 and its MURI Initiative, the US Defense Advanced Research Projects Agency (DARPA) and Army Research Office (ARO) grant W911NF-16-1-0576, the DARPA DRINQs programme, the ARO single investigator award W911NF-19-1-0210, the US National Science Foundation (NSF) PHY1820885 and NSF JILA-PFC PHY-1734006 grants, and the US National Institute of Standards and Technology.

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Correspondence to A. M. Rey.

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Lewis-Swan, R.J., Safavi-Naini, A., Kaufman, A.M. et al. Dynamics of quantum information. Nat Rev Phys 1, 627–634 (2019). https://doi.org/10.1038/s42254-019-0090-y

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