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  • Letter
  • Open Access

Anomaly of continuous symmetries from topological defect network

Qiang Jia2, Ran Luo3, Jiahua Tian1, Yi-Nan Wang3,4,5, and Yi Zhang6

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Phys. Rev. D 114, L041701 – Published 12 August, 2026

DOI: https://doi.org/10.1103/k82f-9npt

Abstract

We show that the ’t Hooft anomaly of a quantum field theory with continuous flavor symmetry can be detected from rearrangements of the topological defect webs implementing the global symmetry in general spacetime dimension, which is concretized in 2D by the F-moves of the defect lines. Via dualizing the defects to flat background gauge field configurations, we characterize the ’t Hooft anomaly by various cohomological data of the symmetry group, where the cohomology of Lie groups with discrete topology plays the central role. We find that an extra dimension emerges naturally as a consequence of the mathematical description of the ’t Hooft anomaly in the case of flat gauging.

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Phys. Rev. D 114, L041701– Published 12 August, 2026
  • Received 23 December 2025
  • Accepted 13 July 2026
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