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arXiv · quant-ph/9711016

On multi-particle entanglement

N Linden·S Popescu
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Abstract

We build, using group-theoretic methods, a general framework for approaching multi-particle entanglement. As far as entanglement is concerned, two states of n spin-1/2 particles are equivalent if they are on the same orbit of the group of local rotations (U(2)^n). We give a method for finding the number of parameters needed to describe inequivalent n spin-1/2 particles states. We also describe how entanglement of states on a given orbit may be characterized by the stability group of the action of the group of local rotations on any point on the orbit.

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N Linden, S Popescu. 1997-11-13. On multi-particle entanglement. https://doi.org/10.1002/(sici)1521-3978(199806)46%3A4%2F5%3C567%3A%3Aaid-prop567%3E3.0.co%3B2-h

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