Graeme Bryce Segal is a Australian-born British mathematician and topologist. He is an Emeritus Senior Research Fellow at All Souls College, Oxford, and a Fellow of the Royal Society (FRS). He previously held the Lowndean Professorship of Astronomy and Geometry at the University of Cambridge and was a Senior Research Fellow at the Mathematical Institute, University of Oxford.
Born in Sydney, Australia, Segal earned his Bachelor of Science at the University of Sydney before moving to Oxford, completing his D.Phil. at St John’s College under the supervision of Sir Michael Atiyah. His research focuses on algebraic topology, K-theory, homotopy theory, infinite-dimensional Lie groups, and the mathematical foundations of quantum field theory and string theory.
Segal formulated the Segal Conjecture in homotopy theory, introduced foundational structures in algebraic K-theory, and developed the mathematical axiomatization of conformal field theory (CFT) and topological quantum field theory (TQFT), commonly known as Segal’s Axioms. He was elected a Fellow of the Royal Society in 1982, awarded the Pólya Prize by the London Mathematical Society in 1990, and received the Royal Society’s Sylvester Medal in 2010.
Segal has periodically engaged with public statements regarding academic freedom and human rights. In 2019, he was among the signatories of a joint declaration sent by “240 Jewish and Israeli scholars to German government,” which argued that non-violent boycotts are a legitimate form of political speech. In 2024, he co-signed “An Open Letter from Concerned Jewish Faculty at the University of Oxford,” addressing Palestinian rights and freedom of expression within higher education.