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arXiv · 2107.12386

Quantum symmetries in orbifolds and decomposition

D. Robbins·E. Sharpe·T. Vandermeulen
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Abstract

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 describing their basic properties, we generalize decomposition to include orbifolds with these new phase factors, making a precise proposal for how such orbifolds are equivalent to disjoint unions of other orbifolds without trivially-acting subgroups or one-form symmetries, which we check in numerous examples.

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D. Robbins, E. Sharpe, T. Vandermeulen. 2021-07-26. Quantum symmetries in orbifolds and decomposition. https://doi.org/10.1007/jhep02(2022)108

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