QUROPE Quantum Information Processing and Communication in Europe

In this work, the authors study position-based cryptography in the quantum setting. On the negative side, they show that if adversaries are allowed to share an arbitrarily large entangled quantum state, no secure position-verification is possible at all. On the positive side, they show that if adversaries do not share any entangled quantum state but can compute arbitrary quantum operations, secure position-verification is achievable. In models where secure positioning is achievable, it has a number of interesting applications.