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arXiv · 0808.0859

The Parts Determine the Whole except for n-Qubit Greenberger-Horne-Zeilinger States

Scott N. Walck·David W. Lyons
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Abstract

The generalized n-qubit Greenberger-Horne-Zeilinger (GHZ) states and their local unitary equivalents are the only pure states of n qubits that are not uniquely determined (among arbitrary states, pure or mixed) by their reduced density matrices of n-1 qubits. Thus, the generalized GHZ states are the only ones containing information at the n-party level.

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Scott N. Walck, David W. Lyons. 2008-08-06. The Parts Determine the Whole except for n-Qubit Greenberger-Horne-Zeilinger States. https://doi.org/10.1103/physreva.79.032326

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