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arXiv · 0912.3825

Breaking and making quantum money: toward a new quantum cryptographic protocol

Andrew Lutomirski·Scott Aaronson·Edward Farhi·David Gosset·Avinatan Hassidim·Jonathan Kelner·Peter Shor
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Abstract

Public-key quantum money is a cryptographic protocol in which a bank can create quantum states which anyone can verify but no one except possibly the bank can clone or forge. There are no secure public-key quantum money schemes in the literature; as we show in this paper, the only previously published scheme [1] is insecure. We introduce a category of quantum money protocols which we call collision-free. For these protocols, even the bank cannot prepare multiple identical-looking pieces of quantum money. We present a blueprint for how such a protocol might work as well as a concrete example which we believe may be insecure.

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Andrew Lutomirski, Scott Aaronson, Edward Farhi, David Gosset, Avinatan Hassidim, Jonathan Kelner, Peter Shor. 2009-12-21. Breaking and making quantum money: toward a new quantum cryptographic protocol. https://arxiv.org/abs/0912.3825

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