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An Improved Quantum Scheduling Algorithm

Lov K. Grover
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Abstract

The scheduling problem consists of finding a common 1 in two remotely located N bit strings. Denote the number of 1s in the string with the fewer 1s by epsilon*N. Classically, it needs at least O(epsilon*N) bits of communication to find the common 1 (ignoring logarithmic factors). The best known quantum algorithm would require O(sqrt(N)) qubits of communication. This paper gives a modified quantum algorithm to find the common 1 with only O(sqrt(epsilon*N)) qubits of communication.

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Lov K. Grover. 2002-02-05. An Improved Quantum Scheduling Algorithm. https://arxiv.org/abs/quant-ph/0202033

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