Deterministic Relativistic Quantum Bit Commitment

Understand

We describe new unconditionally secure bit commitment schemes whose security is based on Minkowski causality and the monogamy of quantum entanglement.

• We first describe an ideal scheme that is purely deterministic, in the sense that neither party needs to generate any secret randomness at any stage.
• We also describe a variant that allows the committer to proceed deterministically, requires only local randomness generation from the receiver, and allows the commitment to be verified in the neighbourhood of the unveiling point.
• We show that these schemes still offer near-perfect security in the presence of losses and errors, which can be made perfect if the committer uses an extra single random secret bit.