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arXiv · 1905.05391

On gapped boundaries for SPT phases beyond group cohomology

Ryohei Kobayashi·Kantaro Ohmori·Yuji Tachikawa
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Abstract

We discuss a strategy to construct gapped boundaries for a large class of symmetry-protected topological phases (SPT phases) beyond group cohomology. This is done by a generalization of the symmetry extension method previously used for cohomological SPT phases. We find that this method allows us to construct gapped boundaries for time-reversal-invariant bosonic SPT phases and for fermionic Gu-Wen SPT phases for arbitrary finite internal symmetry groups.

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Ryohei Kobayashi, Kantaro Ohmori, Yuji Tachikawa. 2019-05-14. On gapped boundaries for SPT phases beyond group cohomology. https://doi.org/10.1007/jhep11(2019)131

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