Abstract

The Universal Blind Quantum Computation (UBQC) protocol allows a client to perform quantum computation on a remote server. In an ideal setting, perfect privacy is guaranteed if the client is capable of producing specific, randomly chosen single qubit states. While from a theoretical point of view, this may constitute the lowest possible quantum requirement, from a pragmatic point of view, generation of such states to be sent along long distances can never be achieved perfectly.

We introduce the concept of ε-blindness for UBQC , in analogy to the concept of ε-security developed for other cryptographic protocols, allowing us to characterize the robustness and security properties of the protocol under possible imperfections. We also present a remote blind single qubit preparation protocol with weak coherent pulses for the client to prepare, in a delegated fashion, quantum states arbitrarily close to perfect random single qubit states, allowing us to efficiently achieve ε-blind UBQC for any ε >0, even if the channel between the client and the server is arbitrarily lossy.

Time permitting, and conditional on the interests of the audience, additional topics related to UBQC can also be discussed.