Sang-hyun (Sam) Kim
Sang-hyun (Sam) Kim
kim.sh
Research Statement (in progress)
The main fields of my research interest are Geometric Group Theory and Low-Dimesional Topology. Particularly, I am interested in finding (or disproving the existence of) closed, hyperbolic surface subgroups in finitely generated groups. The main fuel in this direction is an intriguing question raised by M. Gromov:
Does every one-ended word-hyperbolic group contain a closed, hyperbolic surface group?
The answer to this question is known for Coxeter groups (Gordon-Long-Reid ’04), graphs of free groups with non-trivial rational homologies (Calegari ’08), 3-manifold groups with positive virtual betti numbers or more generally, hyperbolic 3-mainfold groups (Kahn-Markovic ’09). However, the general approach is still widely open. What Henry Wilton and I recently discovered is there is a simple combinatorial property for a word in a free group that provides a sufficient condition for a double of a free group amalgamated along that word contains a surface group. This serves a model case for general one-ended word-hyperbolic groups according to the JSJ-theory of Sela and Bowditch.
Research
Topics in Geometric Group Theory - 2010 (scheduled)
Probability I, Number Theory, Calculus I - 2009;
Discrete Mathematics, Calculus I, Probability I - 2008;
Calculus of Functions of One Variable - 2006;
Introduction to Functions of Several Variables - 2006;
Calculus of Functions of Several Variables - 2001, 2002, 2003, 2004, 2005, 2006
Teaching Experience
Links
Co-Contractions of Graphs and Right-Angled Artin Groups Alg. Geom. Top. 8 (2008)
On Right-Angled Artin Groups Without Surface Subgroups (to appear in Groups, Geometry and Dynamics)
Surface Subgroups of Graph Products of Groups (in preparation)
Polygonal Words in Free Groups (preprint, Joint work with Henry Wilton)
Papers
position
R. H. Bing Instructor,
Department of Mathematics
the University of Texas at Austin
Address
CONtact
OFFICE &
HOURS
Current TEaching
Mail Code C1200
1 University Station
Austin, TX 78712-0257
Tel. +1.512-471-1167
Fax. +1.512-471-9038
RLM 11.164
M 3-4:30, Th 9:30-11