Appears in collection : 2017 - T3 - WS1 - Operator algebras and quantum information theory

Everybody knows that quantum entanglement is monogamous, according to Charles Bennett's wonderful metaphor. However, it has proved surprisingly difficult to capture this intuition in quantitative terms using entanglement measures. We will discuss the few examples of measures where it works out, and show why another, equally intuitive, property, faithfulness of the measure, gets in the way of any attempt at formulating a universal monogamy relation.