Physical Review Letters

Almost Every Pure State of Three Qubits Is Completely Determined by Its Two-Particle Reduced Density Matrices

Noah Linden, Sandu Popescu, William K. Wootters

Published Oct 24, 2002• 147 citations

Abstract

In a system of n quantum particles, we define a measure of the degree of irreducible n-way correlation, by which we mean the correlation that cannot be accounted for by looking at the states of n-1 particles. In the case of almost all pure states of three qubits, we show that there is no such correlation: almost every pure state of three qubits is completely determined by its two-particle reduced density matrices.

DOI: 10.1103/physrevlett.89.207901

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