# Squashed Entanglement, $$\mathbf {k}$$k-Extendibility, Quantum Markov Chains, and Recovery Maps

@article{Li2014SquashedE,
title={Squashed Entanglement, \$\$\mathbf \{k\}\$\$k-Extendibility, Quantum Markov Chains, and Recovery Maps},
author={Ke Li and Andreas J. Winter},
journal={Foundations of Physics},
year={2014},
volume={48},
pages={910-924}
}
• Published 15 October 2014
• Physics
• Foundations of Physics
Squashed entanglement (Christandl and Winter in J. Math. Phys. 45(3):829–840, 2004) is a monogamous entanglement measure, which implies that highly extendible states have small value of the squashed entanglement. Here, invoking a recent inequality for the quantum conditional mutual information (Fawzi and Renner in Commun. Math. Phys. 340(2):575–611, 2015) greatly extended and simplified in various work since, we show the converse, that a small value of squashed entanglement implies that the…
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