Semi-device independent quantum money - Karol Horodecki

The seminal idea of quantum money not forgeable due to laws of Quantum Mechanics proposedby Stephen Wiesner, has laid foundations for the Quantum Information Theory in early ’70s. Recently, several other schemes for quantum currencies have been proposed, all however relying onthe assumption that the mint does not cooperate with the counterfeiter. Drawing inspirations fromthe semi-device independent quantum key distribution protocol, we introduce the first scheme ofquantum money with this assumption partially relaxed, along with the proof of its unforgeability.Significance of this protocol is supported by an impossibility result, which we prove, stating thatthere is no both fully device independent and secure money scheme. Finally, we formulate a quantum analogue of the Oresme-Copernicus-Gresham’s law of economy.