Quantum Blockchain using entanglement in time
This work addresses the challenge of secure and efficient blockchain technology for applications in cryptography and distributed systems, but it is conceptual and incremental as it builds on existing experimental components.
The authors tackled the problem of designing a quantum blockchain by proposing a conceptual method that encodes the blockchain into a temporal GHZ state of photons, leveraging entanglement in time for quantum advantage, with all subcomponents experimentally realized.
We propose a conceptual design for a quantum blockchain. Our method involves encoding the blockchain into a temporal GHZ (Greenberger-Horne-Zeilinger) state of photons that do not simultaneously coexist. It is shown that the entanglement in time, as opposed to an entanglement in space, provides the crucial quantum advantage. All the subcomponents of this system have already been shown to be experimentally realized. Furthermore, our encoding procedure can be interpreted as nonclassically influencing the past.