Among those who make a living from the science of secrecy, worry and paranoia are just signs of professionalism. Can we protect our secrets against those who wield superior technological powers? Can we trust those who provide us with tools for protection? Can we even trust ourselves, our own freedom of choice? Recent developments in quantum cryptography show that some of these questions can be addressed and discussed in precise and operational terms, suggesting that privacy is indeed possible under surprisingly weak assumptions. I will provide an overview of how quantum entanglement, after playing a significant role in the development of the foundations of quantum mechanics, became a new physical resource for all those who seek the ultimate limits of secrecy.
Artur Ekert is a Professor of Quantum Physics at the Mathematical Institute, University of Oxford, UK and a Distinguished Professor at the National University of Singapore. He was a founding Director of the Centre for Quantum Technologies in Singapore. Ekert is one of the pioneers of quantum information science. His invention of entanglement-based quantum cryptography triggered an explosion of research efforts worldwide and continues to inspire new research directions. As well as making the celebrated discovery that Bell’s inequalities can be used to test for eavesdropping, he has contributed to many important advances in the foundations and experimental realisations of quantum communication and computation. He is a recipient of several awards, including the 2019 Micius Prize. He is a Fellow of the Royal Society.