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Measurement of an integral of a classical field with a single quantum particle

Lev Vaidman·Amir Kalev
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Abstract

A method for measuring an integral of a classical field via local interaction of a single quantum particle in a superposition of 2^N states is presented. The method is as efficient as a quantum method with N qubits passing through the field one at a time and it is exponentially better than any known classical method that uses N bits passing through the field one at a time. A related method for searching a string with a quantum particle is proposed.

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Lev Vaidman, Amir Kalev. 2004-06-03. Measurement of an integral of a classical field with a single quantum particle. https://doi.org/10.1103/physreva.71.044303

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