Rate My Professor Mladen Bestvina

Bestvina's research specializes in geometric group theory and geometric topology, with interests including Morse theory and finiteness properties of groups, train tracks and automorphisms of free groups, combination theorems for negatively curved groups, boundaries of negatively curved groups, bounded cohomology of subgroups of mapping class groups, stable actions of groups on real trees, and the Tits alternative for Out(F_n). Key publications include "Morse theory and finiteness properties of groups" with N. Brady (Inventiones mathematicae, 1997), "Train tracks and automorphisms of free groups" with M. Handel (Annals of Mathematics, 1992), "A combination theorem for negatively curved groups" with M. Feighn (Journal of Differential Geometry, 1992), "The boundary of negatively curved groups" with G. Mess (Journal of the American Mathematical Society, 1991), "Bounded cohomology of subgroups of mapping class groups" with K. Fujiwara (Geometry & Topology, 2002), "Train-tracks for surface homeomorphisms" with M. Handel (Topology, 1995), and "The Tits alternative for Out(F_n) I: Dynamics of exponentially-growing automorphisms" with M. Feighn and M. Handel (Annals of Mathematics, 2000). He organizes the Wasatch Topology Conference, maintains a problem list in geometric group theory, and co-organized PCMI 2012. Bestvina received the Simons Fellowship in Mathematics in 2025 for research sabbaticals at the Isaac Newton Institute and SLMath, the Alfred P. Sloan Fellowship in 1988-1989, and the Presidential Young Investigator Award in 1988-1991. His ORCID is 0000-0002-6506-4211. He teaches courses such as Math 6220 Complex Analysis, Math 6210 Real Analysis, and Math 6950 Topics in algebraic topology.