# Anomalies, extensions, and orbifolds

@article{Robbins2021AnomaliesEA, title={Anomalies, extensions, and orbifolds}, author={Daniel Robbins and Eric Sharpe and Thomas Vandermeulen}, journal={Physical Review D}, year={2021} }

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… Expand

#### 3 Citations

Anomaly resolution via decomposition

- Physics
- 2021

In this paper, we apply decomposition to orbifolds with quantum symmetries to resolve anomalies. Briefly, it has been argued by e.g. Wang-Wen-Witten, Tachikawa that an anomalous orbifold can… Expand

Quantum symmetries in orbifolds and decomposition

- Physics
- 2021

In this paper, we introduce a new set of modular-invariant phase factors for orbifolds with trivially-acting subgroups, analogous to discrete torsion and generalizing quantum symmetries. After… Expand

Topological operators, noninvertible symmetries and decomposition

- Physics
- 2021

In this paper we discuss the relationship between noninvertible topological operators, one-form symmetries, and decomposition of two-dimensional quantum field theories, focusing on two-dimensional… Expand

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