Recent work has raised the possibility that quantum information theorytechniques can be used to synchronize atomic clocks nonlocally. One of theproposed algorithms for quantum clock synchronization (QCS) requiresdistribution of entangled pure singlets to the synchronizing parties. Suchremote entanglement distribution normally creates a relative phase error in thedistributed singlet state which then needs to be purified asynchronously. Wepresent a fully relativistic analysis of the QCS protocol which shows thatasynchronous entanglement purification is not possible, and, therefore, thatthe proposed QCS scheme remains incomplete. We discuss possible directions ofresearch in quantum information theory which may lead to a complete, workingQCS protocol.
展开▼
