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arXiv:2511.11343

Global symmetries: locality, unitarity, and regularity

Ibrahima Bah, Shlomo S. Razamat, Michal Shemesh, Hannah Tillim

Published Nov 14, 2025• 0 citations
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Abstract

We study the apparent tension between locality and unitarity for symmetries in quantum field theory. This emerges in the context of categorical symmetries where symmetry operators are generically non-invertible. We argue that locality imposes particular regularities in the action of symmetries on the Hilbert space. This allows us to introduce an observable that can measure the properties of the non-locality for symmetry operators. We study it for a class of examples and demonstrate that this observable can encode data associated to the fusion algebra of symmetries.

DOI
10.48550/arxiv.2511.11343

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