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Security Trade-offs in Ancilla-Free Quantum Bit Commitment in the Presence of Superselection Rules

D. P. DiVincenzo·J. A. Smolin·B. M. Terhal
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Abstract

Security trade-offs have been established for one-way bit commitment in quant-ph/0106019. We study this trade-off in two superselection settings. We show that for an `abelian' superselection rule (exemplified by particle conservation) the standard trade-off between sealing and binding properties still holds. For the non-abelian case (exemplified by angular momentum conservation) the security trade-off can be more subtle, which we illustrate by showing that if the bit-commitment is forced to be ancilla-free an asymptotically secure quantum bit commitment is possible.

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D. P. DiVincenzo, J. A. Smolin, B. M. Terhal. 2004-06-17. Security Trade-offs in Ancilla-Free Quantum Bit Commitment in the Presence of Superselection Rules. https://doi.org/10.1088/1367-2630%2F6%2F1%2F080

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