Secure computation in the Quantum Era
By Ethan
External Mentor: Atul Mantri, Virginia Tech Center for Quantum Information Science and Engineering
This project aims to implement a quantum homomorphic evaluation protocol for computation on encrypted data. In a scenario in which a client delegates computation to a remote server, there are cases in which the client wishes to make use of the server's computing resources while hiding sensitive information from the server. To accomplish this, the client must make use of homomorphic encryption, the ability to evaluate computations on encrypted data without knowing the key or decrypting the data. Thus, the server performs the client's computation without ever knowing the key. Classical fully homomorphic computation has existed for some time, but quantum homomorphic computation—performing encrypted computation in quantum computers—is a newer field. Existing research has presented protocols for a set of basic quantum computation gates known as the Clifford Gates, as well as for the π/8 rotation gate. It is known that this set of gates is capable of achieving universal computation. As a result, being able to compute homomorphically on each of these gates is sufficient for universal homomorphic evaluation. This project examines the practical details of quantum homomorphic evaluation, attempting to simulate a client-server interaction and examine whether the introduction of additional noise to the system due to evaluation poses significant limits to current protocols at large scale.