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Nonlocality improves Deutsch algorithm

Koji Nagata·Sangkyung Lee·Jaewook Ahn
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Abstract

Recently, [{arXiv:0810.3134}] is accepted and published. We show that the Bell inequalities lead to a new type of linear-optical Deutsch algorithms. We have considered a use of entangled photon pairs to determine simultaneously and probabilistically two unknown functions. The usual Deutsch algorithm determines one unknown function and exhibits a two to one speed up in a certain computation on a quantum computer rather than on a classical computer. We found that the violation of Bell locality in the Hilbert space formalism of quantum theory predicts that the proposed {\it probabilistic} Deutsch algorithm for computing two unknown functions exhibits at least a $2\sqrt{2}(\simeq 2.83)$ to one speed up.

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Koji Nagata, Sangkyung Lee, Jaewook Ahn. 2008-11-28. Nonlocality improves Deutsch algorithm. https://arxiv.org/abs/quant-ph/0703132

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