Colloquium – Charles Bennett

Charles Bennett, IBM Research

The quantum nature of information

The information revolution is based on what a physicist would call a classical view of information. Quantum effects were long regarded as a manageable nuisance for information processing, preventing information in microscopic objects from being observed or copied accurately, but are now known to make possible feats like quantum cryptography and potentially dramatic speedups of some computations. More importantly, the quantum approach has led to a more coherent and powerful way of thinking about information. We review this approach, especially the uniquely strong and private kind of correlation known as entanglement, which plays a role in many ways complementary to classical information. Entanglement helps explain the origin of randomness, why the future is more uncertain than the past, and, paradoxically, the macroscopic world’s superficially classical appearance, which allowed quantum laws to remain undiscovered until the 20th century. Its strange beauty, though it eluded Einstein, is within the grasp of any educated person.

Bio: Charles Bennett is a physicist, information theorist and IBM Fellow at IBM Research. Bennett’s recent work at IBM has concentrated on a re-examination of the physical basis of information, applying quantum physics to the problems surrounding information exchange. He has played a major role in elucidating the interconnections between physics and information, particularly in the realm of quantum computation, but also in cellular automata and reversible computing. He discovered, with Gilles Brassard, the concept of quantum cryptography and is one of the founding fathers of modern quantum information theory.

September 11, 2025 @ 4:10pm (CST) in 4327 Stevenson Center; light refreshments available at 3:50 PM

Host: S Pantelides