Exact Thermalization Dynamics in the "Rule 54" Quantum Cellular Automaton.

  title={Exact Thermalization Dynamics in the "Rule 54" Quantum Cellular Automaton.},
  author={Katja Klobas and Bruno Bertini and Lorenzo Piroli},
  journal={Physical review letters},
  volume={126 16},
We study the out-of-equilibrium dynamics of the quantum cellular automaton known as "Rule 54." For a class of low-entangled initial states, we provide an analytic description of the effect of the global evolution on finite subsystems in terms of simple quantum channels, which gives access to the full thermalization dynamics at the microscopic level. As an example, we provide analytic formulas for the evolution of local observables and Rényi entropies. We show that, in contrast to other known… 

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