Catherine Eva Pfaff

Catherine Eva Pfaff is an Assistant Professor in the Department of Mathematics at Queen's University, currently serving as a Member at the Institute for Advanced Study (Princeton, NJ) from September 2024 to July 2025, with an upcoming research invitation at l'Institut des Hautes Études Scientifiques in Paris for Spring 2026.

Her research focuses on geometric group theory, a rich intersection of group theory, geometry, topology, number theory, ergodic theory, and dynamical systems. She has particularly studied the outer automorphism group of the free group via its action on the deformation space of metric graphs, inspired by work on mapping class groups of surfaces. More recently, she has developed interests in topological data analysis, geometric sports analytics, and applications of topological/geometric group theoretic thinking to other fields.

Dr. Pfaff maintains an active research profile with international collaborations, including recent work with Chi Cheuk Tsang on axes decomposition for fully irreducible elements. She has presented at numerous institutions including the University of Hawai'i at Mānoa (July 2025 minicourse) and maintains connections with mathematical luminaries such as Karen Uhlenbeck.

As an educator, she established Directed Reading Programs at Rutgers University and Queen's University, inspired by her experience at the University of Chicago. She takes pride in her students' successes, including Paige Hillen who will begin a postdoc at University of Wisconsin-Madison in fall 2025.

Her academic journey includes a Ph.D. from Rutgers University under Lee Mosher, preceded by undergraduate studies at the University of Chicago where she focused on abstract algebra, geometry, and topology. She has also spent research periods in Barcelona, Marseille, and Bielefeld.