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A feasible quantum communication complexity protocol

Ernesto F. Galvao
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Abstract

I show that a simple multi-party communication task can be performed more efficiently with quantum communication than with classical communication, even with low detection efficiency $η$. The task is a communication complexity problem in which distant parties need to compute a function of the distributed inputs, while minimizing the amount of communication between them. A realistic quantum optical setup is suggested that can demonstrate a five-party quantum protocol with higher-than-classical performance, provided $η>0.33$ .

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Ernesto F. Galvao. 2001-10-01. A feasible quantum communication complexity protocol. https://doi.org/10.1103/physreva.65.012318

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