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arXiv · 2308.08087

Boundary states of a bulk gapped ground state in $2$-d quantum spin systems

Yoshiko Ogata
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Abstract

We introduce a natural mathematical definition of boundary states of a bulk gapped ground state, in the operator algebraic framework of $2$-d quantum spin systems. With approximate Haag duality at the boundary, we derive a $C^*$-tensor category $\tilde{\mathcal{M}}$ out of such boundary state. Under a non-triviality condition of the braiding in the bulk, we show that the Drinfeld center (with an asymptotic constraint) of $\tilde{\mathcal{M}}$ is equivalent to the bulk braided $C^*$-tensor category derived in [14].

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Yoshiko Ogata. 2023-08-16. Boundary states of a bulk gapped ground state in $2$-d quantum spin systems. https://arxiv.org/abs/2308.08087

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