Associate Professor

Department of Mathematical Sciences, Seoul National University

Address : 27-212, Kwanak-dong, Kwanak-ku, Seoul, 151-747

Office : 27- 212      Work phone: (82)2-880-4262

E-mail: slim(at)


Fall 2015 : Topic course in “ Topology, geometry and dynamics on Moduli spaces”

             Reference : A. Zorich, Flat surfaces, G. Forni, C. Matheus, A. Zorich, Lyapunov spectrum of invariant subbundles of the Hodge bundles,

                                   J.C. Yoccoz, Interval Exchange Maps and Translation surfaces, A. Wright, Translation surfaces and their orbit closures

Fall 2015 :  Graduate course in Algebraic Topology I

           Reference : A. Hatcher, Algebraic Topology, P. May, A concise course in algebraic topology

Fall 2014 - Spring 2015 : Sabbatical leave (UC Berkeley and MSRI)

Spring 2014:  Linear Algebra

                       Textbook: Linear Algebra by Friedberg, Insel and Spence
                       Reference: Linear Algebra and Groups by Insuk Lee

Past teaching includes topics in topology, algebraic topology I,II, Intro. to Lie groups, Bernstein seminar in topology and geometric group theory, Intro to Algebra, ergodic theory, etc. More


Research Interest : geometric group theory & dynamics

·         Dynamics of group actions on trees and buildings, more generally metric spaces of non-positive curvature

·         Lattices of Lie groups and automorphism groups of trees and polyhedral complexes, commensurizer subgroups, etc.

·         Entropy rigidity

Seminar organized : Topology & Dynamics


·         Local limit theorem and Martin boundary of Brownian motion (with F. Ledrappier), submitted. arxiv.

·         Integrated multimodal network approach to PET and MRI based on multidimensional persistent homology (with Hyekyong Lee, Dong Soo Lee et al.), submitted. arxiv.

·         Colorings of trees with linear, intermediate and exponential subword complexity (with Seulbee Lee), to appear in J. KMS. pdf

·         Farey map, Diophantine approximation and Bruhat-Tits tree (with Dong Han Kim, Hitoshi Nakada, Rie Natsui), Finite Fields Appl. Vol. 30 (November 2014) page 14-32, arxiv, online

·         Distribution of integral lattice points in an ellipsoid with a diophantine center (with Jiyoung Han, Hyunsuk Kang, Yong-Cheol Kim) J. Number theory, 157 (December 2015), 468-arxiv, online

·         Subword complexity and Sturmian colorings of trees (with Dong Han Kim), to appear in Ergod. Th. & Dynam. Vol 35, no. 2 (April 2015) 461-481. arxiv,  online

·         Hyperbolic tessellation and colorings of trees (with Dong Han Kim), Abstract and applied analysis, vol. 2013, ID 706496 (2013) online

·         On Commensurizer Growth (joint work with Nir Avni and Eran Nevo), Israel J. Math 188. (2012) 259-279 arxiv, online

·         On the distribution of orbits of geometrically finite hyperbolic groups on the boundary (with Hee Oh), Ergod. Th. & Dynam. Sys., Vol 32 (2011), 173-189. online, arxiv

·         Counting overlattices for polyhedral complexes (joint work with A. Thomas), Topology Proceedings, Volume 36 (2010) page 229-247. pdf, online

·         Volume entropy for hyperbolic buildings (joint work with F. Ledrappier), Journal of Modern dynamics, Volume 4, No. 1 (2010) page 139-165. arxiv, online (improved to include all regular buildings)

·         Covering theory for complexes of groups (joint work with A. Thomas), J. Pure Appl. Algebra 212 (2008) 1632-1663. arxiv

·         Minimal volume entropy for graphs, Trans. Amer. Math. Soc. 360 (2008), 5089-5100. arxiv

·         A proof of a L1/2 ergodic theorem (joint work with F. Ledrappier), preprint. pdf (2006)

·         Counting overlattices in automorphism groups of trees, Geom. Dedicata, Vol. 118 (2006), no. 1, pp. 1-21. arxiv


Recent and upcoming talks

·         Colloquium, Seoul National University, Seoul, Korea (December 4, 2015)

·         Colloquium, Ajou University, Suwon, Korea (December 3, 2015)

·         International Conference on Boundaries and Ergodic Geometry, Univ. of Notre Dame, Notre Dame, US (June 3, 2015)

·         Geometry, Topology and Dynamics seminar, UIC, Chicago, US (April 23, 2015)

·         Open-ended seminar, Special program in homogeneous dynamics, MSRI, Berkeley, US (April 21 , 2015)

·         Introductory Workshop: Geometric and Arithmetic Aspects of Homogeneous Dynamics, MSRI, Berkeley, US (February 6, 2015)

·         Geometry and Topology seminar, UC Davis, Davis, US (November 18, 2014)

·         Dynamical Systems Seminar, UT Austin, Austin, US (November 12, 2014)

·         Group actions and Dynamics seminar, Yale University, New Haven, USA (October 27, 2014)

·         Ahlfors-Bers Colloquium, Yale University, New Haven, USA (October 24, 2004)

·         Felix Klein seminar, Univ. of Notre Dame, USA (Oct. 16, 2014)

·         Dynamics seminar, Univ. of  Chicago, Chicago, USA (Oct. 13, 2014)

·         Differential geometry seminar, UC Berkeley, Berkeley, USA (Sept. 22, 2014)

·         Special session on dynamical systems and ordinary differential equations, ICM, Seoul, Korea (August 18, 2014)

·         Geometry on groups and spaces, ICM Satellite conference, Daejeon, Korea (July 11, 2014)

·         KIAS Abel Lecture (Open KIAS Public Lecture), KIAS, Korea (June 20, 2014)

·         Groups and Geometry in the South East, University of Warwick, UK (February 21, 2014)

·         Invited talk, Geometric Topology Fair, Jeonju, Korea (August 12, 2013)

·         Invited talk, Measurable and Topological dynamics session, PRIMA, Shanghai, China (June 25, 2013)

·         Colloquium, Physics Dept. of Seoul University, Seoul, Korea (November 21, 2012)

·         Colloquium, Inha University, Incheon, Korea (October 17, 2012)

·         Oberwolfach Arbeitsgemeinschaft, MFO, Germany (October 12, 2012)

·         Colloquium, Ewha University, Seoul, Korea (September 19, 2012)

·         Geometric Topology Fair, KAIST, Daejun, Korea (August 13, 2012)

·         Intensive lecture series, POSTECH, Korea (July 23-27, 2012)

·         International Conference on Group Actions and its Applications to Geometry, Topology and Analysis, Kunming, China (July 21, 2012)

·         9th KWMS International Conference, Ewha University, Seoul, Korea (June 22, 2012)

·         POSTF workshop, Busan, South Korea (May 19, 2012)

·         Special session on ergodic theory & dynamical systems, KMS spring meeting, Seoul, South Korea (April 28, 2012)

·         Miniworkshop on geometry, KIAS, Seoul, South Korea (December 15, 2011)

·         Mathematics Seminar, KIAS, Seoul, South Korea (December 1, 2011)

·         Topology workshop, Jeonbuk National University, Korea (August 23-24, 2011)

·         Invited talk, Geometric Topology Fair, KAIST, Korea (August 9-10, 2011)

·         Invited talk, Topology session of KMS spring meeting, Seoul, Korea (April 30, 2011)

·         Colloquium, Yonsei University, Seoul, South Korea (Oct. 14, 2010)

·         Hyperbolic geometry and related topics, KIAS, Seoul, South Korea (Sep. 15, 2010)

·         Vogtmannfest, CIRM, France (June 23,2010).

·         Colloquium, Ajou University, Seoul, South Korea (May 14, 2010).

·         Colloquium, Sogang University, Seoul, South Korea (May 7, 2010).

·         Colloquium, POSTECH, Pohang, South Korea (April 2, 2010).

·         Colloquium, Sookmyung Women's University, Seoul, South Korea (November 5, 2009).

·         Colloquium, Seoul National University, Seoul, South Korea (October 6, 2009).

·         Examples of Groups, Ohio State University, Columbus, OH (May 11-14, 2009).

·         Cornell Topology Festival, Ithaca, NY (May 4, 2009).

·         Workshop in rigidity, part of Cornell Topology Festival, Ithaca, NY (May 1, 2009).

·         Joint Mathematics meeting, AMS Special Session on Group Actions on Homogeneous Spaces and Applications, Washington, D.C. (January 5, 2009)

·         Colloquium, Korean Advanced Institute of Science and Technology, Daejeon, South Korea (December 10, 2008)

·         Dynamics of Group Actions Seminar, Yale University (November 10, 2008)

·         Summer School on Quasiconformal analysis and boundaries of hyperbolic groups, Bloomington, Indiana (August 14, 2008) (on the quasi-isometry rigidity result of Bourdon and Pajot, lecture notes)

·         Geometry Seminar, University of Athens, Athens, Greece (August 4, 2008)

·         Analysis and Geometry on Groups Seminar, University Paris 7, Paris, France (July 23, 2008)

·         Geometry Seminar, ETH, Zurich, Switzerland (July 9, 2008)

·         Minicourse on Graphs of Groups and Complexes of Groups, Univ. of Neuchatel, Switzerland (June 2, 9, 16, 23, 2008)

·         Geometry and Dynamics Seminar, Ecole Normale Superieure de Lyon, France (June 18, 2008)

·         Conference on Analysis, Geometry and Dynamics on Groups, Neuchatel, Switzerland (June 13, 2008)

·         Conference on Discrete Groups and Geometric Structures with Applications, Kortrijk, Belgium (May 29, 2008)

·         Dynamics Seminar, Northwestern University (May 13, 2008)

·         AMS Spring Eastern Sectional Meeting, Special Session on Geometric Topology, Courant Institute (Mar. 15-16, 2008)

·         Topology and Geometric Group Theory Seminar, Cornell University (Feb. 26, 2008)

·         Geometry and Topology Seminar, SUNY Buffalo (Feb. 22, 2008)

·         Geometry and Topology Seminar, Binghamton University (February 21, 2008)

·         more

Recent and Upcoming Conferences Organized

·         Geometric Topology Fair, Gyeongju, Korea (August 9-13) (organized by Sang-hyun Kim, Kihyung Ko, Sangjin Lee and Seonhee Lim)

·         2015 CIMPA-NIMS Research School, CIMPA (May 25- June 3, 2015) (organized by Ana Rechtman, Felix Schlenk, Otto van Koert, Seonhee Lim and Urs Frauenfelder).

·         Scientific committee of Young Geometric Group Theory IV, Belgium, Jan 2015 (led by Michelle Bucher-Karlsson).

·         Geometry on groups and spaces (Satellite conference of ICM), KAIST, Daejeon (August 7 12, 2014) (organized by S. Choi, I. Kim, S. Kim, K. Ko, T. Koberda, S. Lim) 

·         KIAS Summer School on Homogeneous Dynamics, KIAS, Seoul (July 2-6, 2013) (organized by Emmanuel Breulliard, Dmitry Kleinbock, Seonhee Lim and Hee Oh).

·         First Joint International Meeting of the AMS and the Korean Mathematical Society, Seoul (December 16-20, 2009). A special session in geometric group theory and low-dimensional topology (and Lie groups).

·         AIM Workshop: Volume Entropy Rigidity, Zurich (June 2009).

·         AMS Western Section Meeting, Special Session on Recent Progress in Geometric Group Theory, San Francisco (April 2009) (Session associated to the invited address of K. Vogtmann).



·         List of conferences in geometric group theory

·         List of conferences in dynamical systems

·         cv