Rate My Professor George Willis

A continuing theme in Willis's research is the interaction between algebra and topology. His early work in functional analysis included demonstrating in 1991 that the compact approximation property for Banach spaces does not imply the approximation property, resolving a 20-year open question. Since 1992, he has pioneered the structure theory of totally disconnected locally compact groups by introducing the notions of scale, tidy subgroups, and flatness, collectively known as 'Willis theory.' This work, surveyed in T. W. Palmer's Banach algebras and the general theory of *-algebras, Volume II (2001), offers original insights into a notoriously intractable subject and connects to ergodic theory, geometric group theory, arithmetic groups, number theory, harmonic analysis, and more. Key publications include the book Introduction to Banach Algebras, Operators, and Harmonic Analysis (2003, co-authored with Dales et al.), chapters such as A totally disconnected invitation to locally compact groups (2023, with Caprace) and Computational Aspects of Totally Disconnected Locally Compact Groups (2025, with Tornier and Ferov), and journal articles like Groups with Flat-Rank Greater Than 1 (2023) and Decomposition Theorems for Automorphism Groups of Trees (2021, with Carter). His contributions have earned him Fellowship of the Australian Academy of Science (2014), the Thomas Ranken Lyle Medal (2025), George Szekeres Medal (2023), Humboldt Research Award (2023), and Gavin Brown Prize (2016). He has delivered plenary lectures at conferences including Banach Algebras 2007 and Locally compact groups beyond Lie theory (2013).