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arXiv · 1107.5881

Quantum Private Information Retrieval with Sublinear Communication Complexity

François Le Gall
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Abstract

This note presents a quantum protocol for private information retrieval, in the single-server case and with information-theoretical privacy, that has O(\sqrt{n})-qubit communication complexity, where n denotes the size of the database. In comparison, it is known that any classical protocol must use \Omega(n) bits of communication in this setting.

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François Le Gall. 2011-07-29. Quantum Private Information Retrieval with Sublinear Communication Complexity. https://doi.org/10.4086/toc.2012.v008a016

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