Anomalies, Extensions and Orbifolds
arXiv:2106.00693 · doi:10.1103/PhysRevD.104.085009
Abstract
We investigate gauge anomalies in the context of orbifold conformal field theories. Such anomalies manifest as failures of modular invariance in the constituents of the orbifold partition function. We review how this irregularity is classified by cohomology and how extending the orbifold group can remove it. Working with such extensions requires an understanding of the consistent ways in which extending groups can act on the twisted states of the original symmetry, which leads us to a discrete-torsion like choice that exists in orbifolds with trivially-acting subgroups. We review a general method for constructing such extensions and investigate its application to orbifolds. Through numerous explicit examples we test the conjecture that consistent extensions should be equivalent to (in general multiple copies of) orbifolds by non-anomalous subgroups.
arXiv comment37 pages, 2 appendices, 3 figures
References in corpus (12)
- Topological Defect Lines and Renormalization Group Flows in Two Dimensions
- On gauging finite subgroups
- Cluster decomposition, T-duality, and gerby CFT's
- Symmetric Gapped Interfaces of SPT and SET States: Systematic Constructions
- Modified instanton sum in QCD and higher-groups
- Undoing decomposition
- Anomaly resolution via decomposition
- Quantum symmetries in orbifolds and decomposition
- The Moonshine Anomaly
- Generalised Mathieu Moonshine
- A generalization of decomposition in orbifolds
- Orbifolds from Modular Orbits
Cited by in corpus (11)
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- Quantum symmetries in orbifolds and decomposition
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- Orbifolds by 2-groups and decomposition
- Combinatoric topological string theories and group theory algorithms
- Decomposition and the Gross-Taylor string theory
- Decomposition in Chern-Simons theories in three dimensions
- Dilaton shifts, probability measures, and decomposition
- Decomposition squared
- Anomaly resolution by non-invertible symmetries
- Perspectives on Anomaly Resolution