# Boundary-bulk relation in topological orders

@article{Kong2017BoundarybulkRI, title={Boundary-bulk relation in topological orders}, author={Liang Kong and X. Wen and Hao Zheng}, journal={Nuclear Physics}, year={2017}, volume={922}, pages={62-76} }

Abstract In this paper, we study the relation between an anomaly-free n + 1 D topological order, which are often called n + 1 D topological order in physics literature, and its n D gapped boundary phases. We argue that the n + 1 D bulk anomaly-free topological order for a given n D gapped boundary phase is unique. This uniqueness defines the notion of the “ bulk ” for a given gapped boundary phase. In this paper, we show that the n + 1 D “ bulk ” phase is given by the “center” of the n D… Expand

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