Quantum Bit Commitment can be Unconditionally Secure

TL;DR

This paper challenges the prevailing belief that unconditionally secure quantum bit commitment is impossible, demonstrating a method to circumvent the no-go theorem and establish its theoretical feasibility.

Contribution

It reveals that the no-go theorem does not conclusively prove the impossibility of unconditionally secure QBC and provides a proof of its potential security.

Findings

Circumvents the no-go theorem for QBC

Proves unconditionally secure QBC is possible

Challenges existing assumptions in quantum cryptography

Abstract

It is generally believed that unconditionally secure quantum bit commitment (QBC) is proven impossible by a "no-go theorem". We point out that the theorem only establishes the existence of a cheating unitary transformation in any QBC scheme secure against the receiver, but this fact alone is not sufficient to rule out unconditionally secure QBC as a matter of principle, because there exists no proof that the cheating unitary transformation must be known to the cheater in all possible cases. In this work, we show how to circumvent the "no-go theorem" and prove that unconditionally secure QBC is in fact possible.