# Quantum Private Information Retrieval has Linear Communication Complexity

@article{Baumeler2014QuantumPI,
title={Quantum Private Information Retrieval has Linear Communication Complexity},
author={{\"A}min Baumeler and Anne Broadbent},
journal={Journal of Cryptology},
year={2014},
volume={28},
pages={161-175}
}
• Published 19 April 2013
• Computer Science
• Journal of Cryptology
In private information retrieval (PIR), a client queries an $$n$$n-bit database in order to retrieve an entry of her choice, while maintaining privacy of her query value. Chor et al. [J ACM 45(6):965–981, 1998] showed that, in the information-theoretical setting, a linear amount of communication is required for classical PIR protocols (thus the trivial protocol is optimal). This linear lower bound was shown by Nayak [FOCS 1999, pp. 369–376, 1999] to hold also in the quantum setting. Here, we…
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