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Title: Entangled quantum cellular automata, physical complexity, and Goldilocks rules
Cellular automata are interacting classical bits that display diverse behaviors, from fractals to random-number generators to Turing-complete computation. We introduce entangled quantum cellular automata subject to Goldilocks rules, tradeoffs of the kind underpinning biological, social, and economic complexity. Tweaking digital and analog quantum-computing protocols generates persistent entropy fluctuations; robust dynamical features, including an entangled breather; and network structure and dynamics consistent with complexity. Present-day quantum platforms---Rydberg arrays, trapped ions, and superconducting qubits---can implement Goldilocks protocols, which generate quantum many-body states with rich entanglement and structure. Moreover, the complexity studies reported here underscore an emerging idea in many-body quantum physics: some systems fall outside the integrable/chaotic dichotomy.  more » « less
Award ID(s):
1839232
PAR ID:
10197517
Author(s) / Creator(s):
Date Published:
Journal Name:
ArXivorg
ISSN:
2331-8422
Page Range / eLocation ID:
2005.01763
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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