activity
20232025
collaborators

5 papers

math.GT2025

Asymptotically rigid mapping class groups of infinite graphs

Thomas Hill, Sanghoon Kwak, Brian Udall +1

We introduce and study asymptotically rigid mapping class groups of certain infinite graphs. We determine their finiteness properties and show that these depend on the number of en…

math.GT2024

Surfaces proper homotopy equivalent to graphs and their Dehn-Nielsen-Baer maps

Ryan Dickmann, Hannah Hoganson, Sanghoon Kwak

Motivated by the recent work of Algom-Kfir and Bestinva introducing the mapping class group of an infinite graph via proper homotopy equivalences, we give a necessary and sufficien…

math.GR2024

Nonunique Ergodicity on the Boundary of Outer space

Mladen Bestvina, Elizabeth Field, Sanghoon Kwak

To an -tree in the boundary of Outer space, we associate two simplices: the simplex of projective length measures, and the simplex of projective dual currents. For both…

math.GT2023

Coarsely bounded generating sets for mapping class groups of infinite-type surfaces

Thomas Hill, Sanghoon Kwak, Rebecca Rechkin

Mann and Rafi's seminal work initiated the study of the coarse geometry of big mapping class groups. Specifically, they construct coarsely bounded (CB) generating sets for mapping…

math.GR2023

Generating Sets and Algebraic Properties of Pure Mapping Class Groups of Infinite Graphs

George Domat, Hannah Hoganson, Sanghoon Kwak

We completely classify the locally finite, infinite graphs with pure mapping class groups admitting a coarsely bounded generating set. We also study algebraic properties of the pur…