Adrian Kent
Adrian Kent is a British theoretical physicist. He is a professor at the University of Cambridge, member of the Centre for Quantum Information and Foundations, and Distinguished Visiting Research Chair at the Perimeter Institute for Theoretical Physics. His research focuses on quantum foundations, quantum information science, and quantum cryptography. In 1999 he published the first information-theoretically secure protocols for bit commitment and coin flipping, which were also the first relativistic cryptographic protocols. He is a co-inventor of quantum tagging, or quantum position authentication, providing the first schemes for position-based quantum cryptography. In 2005 he published with Lucien Hardy and Jonathan Barrett the first security proof of quantum key distribution based on the no-signalling principle.
Work
Field theory
Kent's early contributions to physics were on topics related to conformal field theory. Together with Peter Goddard and David Olive, he introduced the coset construction classifying unitary highest weight representations of the Virasoro algebra, and described the Virasoro algebra's singular vectors. In addition, he investigated the representation theory of superconformal algebras.Quantum cryptography
Kent is inventor of the field of relativistic quantum cryptography, where security of the cryptographic tasks is guaranteed from the properties of quantum information and from the relativistic physical principle stating that information cannot travel faster than the speed of light. In 1999 he published the first unconditionally secure protocols for bit commitment and strong coin tossing, relativistic protocols that evade no-go theorem by Mayers, Lo and Chau, and by Lo and Chau, respectively. He is a co-inventor of quantum tagging, or quantum position authentication, where the properties of quantum information and the no-signalling principle are used to authenticate the location of an object.He published with Lucien Hardy and Jonathan Barrett the first security proof for quantum key distribution based on the no-signalling principle, where two parties can generate a secure secret key even if their devices are not trusted and they are not described by quantum theory, as long as they satisfy the no-signalling principle. With Roger Colbeck, he invented quantum randomness expansion, a task where an initial private random string is expanded into a larger private random string.