, Volume 22, Issue 2, pp 493–499 | Cite as

Mapping cones and separable states

  • Erling Størmer


We study mapping cones and their dual cones of positive maps of the \(n\times n\) matrices into itself. For a natural class of cones there is a close relationship between maps in the cone, super-positive maps, and separable states. In particular the composition of a map from the cone with a map in the dual cone is super-positive, and so the natural state it defines is separable.


Positive maps Mapping cones Separable states 

Mathematics Subject Classification

46L60 46L99 15A04 



The author is indebted to Geir Dahl for helpful comments on dual cones.


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Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  1. 1.Department of MathematicsUniversity of OsloOsloNorway

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