Geometrical aspects of entanglement

  title={Geometrical aspects of entanglement},
  author={Jon Magne Leinaas and Jan Myrheim and Eirik Ovrum},
  journal={Physical Review A},
We study geometrical aspects of entanglement, with the Hilbert–Schmidt norm defining the metric on the set of density matrices. We focus first on the simplest case of two two-level systems and show that a “relativistic” formulation leads to a complete analysis of the question of separability. Our approach is based on Schmidt decomposition of density matrices for a composite system and nonunitary transformations to a standard form. The positivity of the density matrices is crucial for the method… 
The aspects of many particle systems, as far as their entanglement is concerned, is highlighted. To this end we briefly review the bipartite measures of entanglement and the entanglement of pairs
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