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Optimal classical-communication-assisted local model of n-qubit Greenberger-Horne-Zeilinger correlations

Tracey E. Tessier·Carlton M. Caves·Ivan H. Deutsch·Dave Bacon·Bryan Eastin
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Abstract

We present a model, motivated by the criterion of reality put forward by Einstein, Podolsky, and Rosen and supplemented by classical communication, which correctly reproduces the quantum-mechanical predictions for measurements of all products of Pauli operators on an n-qubit GHZ state (or ``cat state''). The n-2 bits employed by our model are shown to be optimal for the allowed set of measurements, demonstrating that the required communication overhead scales linearly with n. We formulate a connection between the generation of the local values utilized by our model and the stabilizer formalism, which leads us to conjecture that a generalization of this method will shed light on the content of the Gottesman-Knill theorem.

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Tracey E. Tessier, Carlton M. Caves, Ivan H. Deutsch, Dave Bacon, Bryan Eastin. 2005-05-26. Optimal classical-communication-assisted local model of n-qubit Greenberger-Horne-Zeilinger correlations. https://doi.org/10.1103/physreva.72.032305

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