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arXiv · 2508.16721

Symmetries, anomalies, and dualities of two-dimensional Non-Linear Sigma Models

Guillermo Arias-Tamargo·Maxwell L. Velásquez Cotini Hutt
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Abstract

We analyse the global symmetry structure of two-dimensional Non-Linear Sigma Models with Wess-Zumino term. When the target space has a compact isometry without fixed points, the theory has a pair of (group-like) global symmetries and many such theories also have non-invertible symmetries. We describe how the topology of the target space and Wess-Zumino term determine whether the group-like symmetries are continuous or discrete, and study their pure and mixed 't Hooft anomalies. We also revisit the construction of the non-invertible symmetries, which are associated with possible self-dualities under discrete gauging, and show how the global symmetry structure is left invariant by this gauging.

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Guillermo Arias-Tamargo, Maxwell L. Velásquez Cotini Hutt. 2025-08-22. Symmetries, anomalies, and dualities of two-dimensional Non-Linear Sigma Models. https://arxiv.org/abs/2508.16721

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