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arXiv · 1405.5946

Entanglement of Local Operators in large N CFTs

Pawel Caputa·Masahiro Nozaki·Tadashi Takayanagi
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Abstract

We study Renyi and von-Neumann entanglement entropy of excited states created by local operators in large N (or large central charge) CFTs. First we point that a naive large N expansion can break down for the von-Neumann entanglement entropy, while it does not for the Renyi entanglement entropy. This happens even for the excited states in free Yang-Mills theories. Next, we analyze strongly coupled large N CFTs from both field theoretic and holographic viewpoints. We find that the Renyi entanglement entropy of the excited state produced by a local operator, grows logarithmically under its time evolution and its coefficient is proportional to the conformal dimension of the local operator.

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Pawel Caputa, Masahiro Nozaki, Tadashi Takayanagi. 2014-05-23. Entanglement of Local Operators in large N CFTs. https://doi.org/10.1093/ptep/ptu122

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