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arXiv · 2110.06932

Chiral central charge from a single bulk wave function

Isaac H. Kim·Bowen Shi·Kohtaro Kato·Victor V. Albert
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Abstract

A $(2+1)$-dimensional gapped quantum many-body system can have a topologically protected energy current at its edge. The magnitude of this current is determined entirely by the temperature and the chiral central charge, a quantity associated with the effective field theory of the edge. We derive a formula for the chiral central charge that, akin to the topological entanglement entropy, is completely determined by the many-body ground state wave function in the bulk. According to our formula, nonzero chiral central charge gives rise to a topological obstruction that prevents the ground state wave function from being real-valued in any local product basis.

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Isaac H. Kim, Bowen Shi, Kohtaro Kato, Victor V. Albert. 2021-10-13. Chiral central charge from a single bulk wave function. https://doi.org/10.1103/physrevlett.128.176402

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