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arXiv · 2507.16475

On two-dimensional tensor network group symmetries

José Garre-Rubio·András Molnár
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Abstract

We introduce two-dimensional tensor network representations of finite groups carrying a 4-cocycle index. We characterize the associated gapped (2+1)D phases that emerge when these anomalous symmetries act on tensor network ground states. We further develop related tensor network unitaries that generate symmetric states representing (3+1)D symmetry protected topological phases. Although aspects of these constructions have been previously addressed, our contribution unifies them within a single tensor network framework and emphasizes the explicit formulation of local tensor equations encoding global consistency conditions.

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José Garre-Rubio, András Molnár. 2025-07-22. On two-dimensional tensor network group symmetries. https://arxiv.org/abs/2507.16475

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