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Entangled quantum cellular automata, physical complexity, and Goldilocks rules

Hillberry, Logan E. and Jones, Matthew T. and Vargas, David L. and Rall, Patrick and Yunger Halpern, Nicole and Bao, Ning and Notarnicola, Simone and Montangero, Simone and Carr, Lincoln D. (2021) Entangled quantum cellular automata, physical complexity, and Goldilocks rules. Quantum Science and Technology, 6 (4). Art. No. 045017. ISSN 2058-9565. doi:10.1088/2058-9565/ac1c41.

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Cellular automata are interacting classical bits that display diverse emergent behaviors, from fractals to random-number generators to Turing-complete computation. We discover that quantum cellular automata (QCA) can exhibit complexity in the sense of the complexity science that describes biology, sociology, and economics. QCA exhibit complexity when evolving under 'Goldilocks rules' that we define by balancing activity and stasis. Our Goldilocks rules generate robust dynamical features (entangled breathers), network structure and dynamics consistent with complexity, and persistent entropy fluctuations. Present-day experimental platforms—Rydberg arrays, trapped ions, and superconducting qubits—can implement our Goldilocks protocols, making testable the link between complexity science and quantum computation exposed by our QCA.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Hillberry, Logan E.0000-0003-0515-8280
Jones, Matthew T.0000-0001-9358-2502
Rall, Patrick0000-0001-8596-5933
Yunger Halpern, Nicole0000-0001-8670-6212
Bao, Ning0000-0002-3296-1039
Carr, Lincoln D.0000-0002-4848-7941
Additional Information:© 2021 The Author(s). Published by IOP Publishing Ltd. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. Received 13 July 2021. Accepted 10 August 2021. Published 29 September 2021. The authors thank Clarisa Benett, Haley Cole, Daniel Jaschke, Eliot Kapit, Evgeny Mozgunov, and Pedram Roushan for useful conversations. This work was performed in part with support by the NSF under Grants OAC-1740130, CCF-1839232, PHY-1806372, and PHY-1748958; and in conjunction with the QSUM program, which is supported by the Engineering and Physical Sciences Research Council Grant EP/P01058X/1. This work is partially supported by the Italian PRIN 2017, the Horizon 2020 research and innovation programme under Grant Agreement No. 817482 (PASQuanS). NYH is grateful for funding from the Institute for Quantum Information and Matter, an NSF Physics Frontiers Center (NSF Grant PHY-1125565) with support of the Gordon and Betty Moore Foundation (GBMF-2644), for a Barbara Groce Graduate Fellowship, and for an NSF grant for the Institute for Theoretical Atomic, Molecular, and Optical Physics at Harvard University and the Smithsonian Astrophysical Observatory. Data availability statement. The data that support the findings of this study are available upon reasonable request from the authors.
Group:Institute for Quantum Information and Matter
Funding AgencyGrant Number
Engineering and Physical Sciences Research Council (EPSRC)EP/P01058X/1
Ministero dell'Istruzione, dell'Università e della Ricerca (MIUR)PRIN 2017
European Research Council (ERC)817482
Gordon and Betty Moore FoundationGBMF-2644
Barbara Groce Graduate Fellowship, CaltechUNSPECIFIED
Issue or Number:4
Record Number:CaltechAUTHORS:20211012-211827418
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Official Citation:Logan E Hillberry et al 2021 Quantum Sci. Technol. 6 045017
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:111373
Deposited By: George Porter
Deposited On:14 Oct 2021 14:24
Last Modified:14 Oct 2021 14:24

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