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arXiv · 1512.05945

Entanglement and topological interfaces

Enrico M. Brehm·Ilka Brunner·Daniel Jaud·Cornelius Schmidt-Colinet
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Abstract

In this paper we consider entanglement entropies in two-dimensional conformal field theories in the presence of topological interfaces. Tracing over one side of the interface, the leading term of the entropy remains unchanged. The interface however adds a subleading contribution, which can be interpreted as a relative (Kullback-Leibler) entropy with respect to the situation with no defect inserted. Reinterpreting boundaries as topological interfaces of a chiral half of the full theory, we rederive the left/right entanglement entropy in analogy with the interface case. We discuss WZW models and toroidal bosonic theories as examples.

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Enrico M. Brehm, Ilka Brunner, Daniel Jaud, Cornelius Schmidt-Colinet. 2016-02-25. Entanglement and topological interfaces. https://doi.org/10.1002/prop.201600024

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