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Quantum algorithm for distributed clock synchronization

Isaac Chuang
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Abstract

The clock synchronization problem is to determine the time difference $Δ$ between two spatially separated clocks. When message delivery times between the two clocks are uncertain, $O(2^{2n})$ classical messages must be exchanged between the clocks to determine $n$ digits of $Δ$. On the other hand, as we show, there exists a quantum algorithm to obtain $n$ digits of $Δ$ while communicating only O(n) quantum messages.

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Isaac Chuang. 2000-05-22. Quantum algorithm for distributed clock synchronization. https://doi.org/10.1103/physrevlett.85.2006

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