# Geometrical aspects of entanglement

@article{Leinaas2006GeometricalAO, title={Geometrical aspects of entanglement}, author={Jon Magne Leinaas and Jan Myrheim and Eirik Ovrum}, journal={Physical Review A}, year={2006}, volume={74}, pages={012313} }

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…

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