Secure Quantum Bit Commitment Using Unstable Qubits

Chi-Yee Cheung

Published Mar 17, 2006• 0 citations

Abstract

Using unstable particles (such as neutrons and muons) as qubits, we propose a quantum bit commitment protocol that is humanly impossible to break. Neutrons and muons decay by emitting neutrinos which carry away quantum information, but their interaction with matter is so weak that it would take an astronomically-sized machine just to catch them, not to mention performing controlled unitary operations on them. As a result quantum information is lost, and cheating is not possible even if the participants had access to the most powerful quantum computers that could ever be built. Therefore, for all practical purposes, our new protocol is as good as unconditionally secure.

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