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arXiv · 2509.18262

Training the classification capability of large-scale quantum cellular automata

Mario Boneberg·Simon Kochsiek·Gabriele Perfetto·Igor Lesanovsky
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Abstract

In the vicinity of a phase transition ergodicity can be broken. Here, different initial many-body configurations evolve towards one of several fixed points, which are macroscopically distinguishable through an order parameter. This mechanism enables state classification in quantum cellular automata and feed-forward quantum neural networks. We demonstrate that this capability can be efficiently learned from training data even in extremely high-dimensional state spaces. We illustrate this using a quantum cellular automaton that allows binary classification, which is closely connected to the dynamics of a $\mathbb{Z}_2$-symmetric Ising model with local interactions and dissipation. This approach can be generalized beyond binary classification and offers a natural framework for exploring the link between emergent many-body phenomena and the interpretation of data processing capabilities in the context of quantum machine learning.

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Mario Boneberg, Simon Kochsiek, Gabriele Perfetto, Igor Lesanovsky. 2025-09-22. Training the classification capability of large-scale quantum cellular automata. https://arxiv.org/abs/2509.18262

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