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arXiv · 2112.01854

Superintegrable cellular automata and dual unitary gates from Yang-Baxter maps

Abstract

We consider one dimensional block cellular automata, where the local update rules are given by Yang-Baxter maps, which are set theoretical solutions of the Yang-Baxter equations. We show that such systems are superintegrable: they possess an exponentially large set of conserved local charges, such that the charge densities propagate ballistically on the chain. For these quantities we observe a complete absence of "operator spreading". In addition, the models can also have other local charges which are conserved only additively. We discuss concrete models up to local dimensions $N\le 4$, and show that they give rise to rich physical behaviour, including non-trivial scattering of particles and the coexistence of ballistic and diffusive transport. We find that the local update rules are classical versions of the "dual unitary gates" if the Yang-Baxter maps are non-degenerate. We discuss consequences of dual unitarity, and we also discuss a family of dual unitary gates obtained by a non-integrable quantum mechanical deformation of the Yang-Baxter maps.

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BibTeXRIS

Tamás Gombor, Balázs Pozsgay. 2021-12-03. Superintegrable cellular automata and dual unitary gates from Yang-Baxter maps. https://doi.org/10.21468/scipostphys.12.3.102

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