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arXiv · 2609.20725

Superselection theory for 2D braided quantum spin systems via Connes fusion

Gregory Faurot·Charlton Li·David Penneys·Emeline Sherman
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Abstract

The article arXiv:2410.21454 constructed a braided $\mathrm{W^*}$-tensor category of superselection sectors associated to a net of von Neumann algebras on a suitably geometric poset using localized and transportable endomorphisms. In this article, we construct an equivalent tensor product and braiding using the Connes fusion tensor product without localizing, using ideas from arXiv:1812.04470 for conformal nets. As an application, we prove that the category of superselection sectors associated to the 2D braided quantum spin system constructed from a unitary braided fusion category $\mathcal{B}$ in arXiv:2506.19969 is equivalent to $\mathsf{Hilb}(\mathcal{B})^{\rm op}$, the opposite of the unitary ind-completion of $\mathcal{B}$, as a braided $\mathrm{W^*}$-tensor category.

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Gregory Faurot, Charlton Li, David Penneys, Emeline Sherman. 2026-09-17. Superselection theory for 2D braided quantum spin systems via Connes fusion. https://arxiv.org/abs/2609.20725

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