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Greenberger-Horne-Zeilinger paradoxes for many qudits

Nicolas J. Cerf·Serge Massar·Stefano Pironio
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Abstract

We construct GHZ contradictions for three or more parties sharing an entangled state, the dimension d of each subsystem being an even integer greater than 2. The simplest example that goes beyond the standard GHZ paradox (three qubits) involves five ququats (d=4). We then examine the criteria a GHZ paradox must satisfy in order to be genuinely M-partite and d-dimensional.

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Nicolas J. Cerf, Serge Massar, Stefano Pironio. 2001-07-05. Greenberger-Horne-Zeilinger paradoxes for many qudits. https://doi.org/10.1103/physrevlett.89.080402

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