Nonlocal parameters for multiparticle density matrices

N Linden, S Popescu, A Sudbery

Research output: Contribution to journalArticle (Academic Journal)


As far as entanglement is concerned, two density matrices of n particles are completely equivalent if one can be transformed into the other by local unitary transformations. We present two methods to find whether or not two generic density matrices of arbitrary numbers of spin-1/2 particles are equivalent. Both methods describe density matrices in terms of a finite number of invariant parameters.

Original languageEnglish
Pages (from-to)243-247
Number of pages5
JournalPhysical Review Letters
Issue number2
Publication statusPublished - 12 Jul 1999

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