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arXiv · 1105.4032

A quantum no-reflection theorem and the speeding up of Grover's search algorithm

Karthikeyan S. Kumar·G. S. Paraoanu
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Abstract

We prove that it is impossible to built a universal quantum machine that produces reflections about an unknown state. We then point out a connection between this result and the optimality of Grover's search algorithm: if such reflection machines were available, it would be possible to accelerate Grover's search algorithm to exponential speedups.

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Karthikeyan S. Kumar, G. S. Paraoanu. 2011-05-20. A quantum no-reflection theorem and the speeding up of Grover's search algorithm. https://doi.org/10.1209/0295-5075%2F93%2F64002

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