Letters in Mathematical Physics

, Volume 101, Issue 1, pp 1–11 | Cite as

Bounds for Entanglement via an Extension of Strong Subadditivity of Entropy

  • Eric A. Carlen
  • Elliott H. Lieb


Let ρ 12 be a bipartite density matrix. We prove lower bounds for the entanglement of formation Ef(ρ 12) and the squashed entanglement Esq(ρ 12) in terms of the conditional entropy S 12S 1 and prove that these bounds are sharp by constructing a new class of states whose entanglements can be computed, and for which the bounds are saturated.

Mathematics Subject Classification

82P45 47A63 


entropy entanglement strong subadditivity 


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Copyright information

© The Author(s) 2012

Authors and Affiliations

  1. 1.Department of Mathematics, Hill CenterRutgers UniversityPiscatawayUSA
  2. 2.Departments of Mathematics and Physics, Jadwin HallPrinceton UniversityPrincetonUSA

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