Research

Index   Teaching  Links

Conferences and Workshop  Talks Preprints Selected Publications Books Travel Plans

Reviews

Graduate student homepage : Their research papers, presentations, and so on and our workshops.

For admissions to KAIST, please see: http://www.kaist.ac.kr/kr/html/admission/0201.html  or  https://www.kaist.ac.kr/en/html/admission/0201.html  

 

 

Helpful sites for graduate students in mathematics: mathstackexchange, mathoverflow, encyclopedia of mathematics, mathsurvey.org

Conferences and workshops: organizations (more in Graduate student homepage)

KAIST Geometric Structures Lecture Series, Zoom Lecture Series for Graduate Students

2024 JNU/KAIST/SNU Geometry & Topology Workshop (5th), (Aug. 19-23, 2024) Workshop, Daejeon, South Korea

2023 JNU/KAIST/SNU Geometry & Topology Workshop (4th), (Aug. 16-18, 2023) Workshop, Daejeon, South Korea

The 3rd JNU-KAIST Geometric Topology Fair, (Oct 18-22, 2021) Virtual workshop, South Korea

The 2nd JNU-KAIST Geometric Topology Fair, (July 8-14, 2018) Jeju National University, South Korea

JNU-KAIST Geometric Topology Fair, (June 12-16, 2017) Jeju National University, South Korea

Geometric Structures and Character Varieties, (December 28-30, 2015) Jeju National University, South Korea

Workshop on Geometric Structures, Hitchin Components and Representation Varieties, (October 20 - 24, 2015) KIAS, Seoul, Korea

 ICM 2014 Satellite Conference: Geometry on Groups and Spaces, (August 7 – 12, 2014) KAIST(Daejeon) Videos of invited talks is available here.

The 11th KAIST Geometric Topology Fair, August 12 - 6, Jeonju, Korea  

The 10th KAIST Geometric Topology Fair, Daejeon, August 13-17, 2012

Selected Talks

Closed affine manifolds with partially hyperbolic linear holonomy, Discrete Subgroups of Lie Groups (19w5040), Banff International Research Station (December 10, 2019), Topology Seminar, Univ. Texas, Austin (January 28, 2020), Topology, Algebraic Geometry, and Dynamics Seminar, George Mason University (February 7th, 2020),

Lens-shaped totally geodesic ends of convex real projective manifolds, Geometry and Topology Seminar, School of Mathematics and Statistics, University of Sydney (December 11, 2018), Topology and Geometry Seminar, Florida State University (February 4th, 2020), Geometry/Geometric Analysis Seminar, Purdue University (February 11th, 2020)

Margulis space-time with parabolics, JNU-KAIST Geometric topology fair (June 13,15, 2018)

Deformations of convex real projective structures on orbifolds, AMS-TIMC joint meeting, Banaras Hindu University (December 16, 2016)

Tropical computational experiments with compactifications of the deformation spaces of convex real projective structures on 2-orbifolds and surfaces, Avignon talk (Feb 23, 2016) (Here I show that the compactification dimension always collapses. The talk I gave in GMU August 2015 was not correct in this part.)

Compactifications of Margulis space-times, RIMS, Kyoto, Japan (December 14-18, 2015)

The deformation spaces of convex real projective structures on manifolds or orbifolds with ends: openness and closedness, Topology seminar, UCSB (June 9, 2015) Geometry/Topology Seminar UC Davis (May 14 2015)

The ends of convex real projective manifolds and orbifolds, Geometry/Topology Seminar UC Davis (April 28, 2015)

An introduction to convex real projective manifolds (orbifolds), Univ. Texas Pan American (January 30, 2014)

Deforming convex RP3-structures on 3-orbifolds, Boston University (October 23, 2012), Ohio State University (October 25, 2012)

The topological and geometrical finiteness of complete flat Lorentzian 3-manifolds with free fundamental groups, CRM, Montreal (October 16, 2012)

Deforming convex real projective 3-orbifolds, Oxford University, MOS Newton Institute Workshop (March 17, 2011)

Spherical triangles and the two components of the SO(3)-character space of the fundamental group of a closed surface of genus 2, A talk at a workshop in IMA, NUS Singapore (July, 2010)

Hyperbolic geometry: algorithmic, number theoretic and numerical aspects, (A graduate student workshop ) NIMS-KIAS workshop at KIAS, Seoul (March 15-19, 2010) Notes of my talk.

Real projective structures on 3-orbifolds and projective invariants, Melbourne Talk (May 18, 2009)

Preprints

The volumes of PSL(n, R)-Hitchin Riemann moduli spaces are infinite, ArXiv:2305.10093, submitted

RPn#RPn admits no RPn-structure, ArXiv:2209.02924, submitted

Complete affine manifolds with Anosov holonomy groups, ArXiv:2009.11127, submitted

Monograph: ``Real projective orbifolds with ends and their deformation spaces: the deformation theory for the nice ones'' draft (March 2024), submitted but currently under revision, mathematica files: coefficientsol8-inpaper.nb, equations.nb, , exampletet3.nb, ,quasijoin2.nb 

The PL-methods for hyperbolic 3-manifolds to prove tameness, February, 2006 (I will not publish this article in this context.)

Selected Publications

Symplectic coordinates on the deformation spaces of convex projective structures on 2-orbifolds, (with Hongtaek Jung) ArXiv:2007.13285, Transformation Group 28 (2023) 639–693, Dec.

Tameness of Margulis space-times with parabolics, (with Todd Drumm, William Goldman) Forum Mathematicum 35 No.1 (2022), 1-59. Nov., ArXiv:1710.09162, mathematica files:  Calculus-v2.nb , convergencesII-v2.nb, FoliationsV2.nb, geodesicFinal-v2.nb, NewNormalComp-v3.nb , NewNormalComp2-v3.nb, StandardFormII-v4.nb, Vanalysis-v2.nb

Deformation spaces of Coxeter truncation polytopes, (with Gye-Seon Lee, Ludovic Marquis) ArXiv:2108.11689, J. London Math. Soc. 106 No.4 (2022) 3822-3864, Dec.

Symplectic coordinates on PSL3(ℝ)-Hitchin components, (with Hongtaek Jung, Hong Chan Kim) Pure and Applied Mathematics Quarterly 16. no. 5 (2020) 1321-1386 arXiv:1901.04651

Convex projective generalized Dehn fillings, (with Gye-Seon Lee, Ludovic Marquis) Annales Scientifiques de l'Ens 53 no 1.(2020) 217-266 arXiv:1611.02505

Convex and concave decompositions of affine 3-manifolds, Bulletin of the Brazilian Mathematical Society, New Series volume 51 (2020), 243–291 arXiv:1411.1273

Deformations of convex real projective structures on manifolds and orbifolds, (with Gye-Seon Lee, Ludovic Marquis) arXiv:1605.02548, Handbook of Group Actions III, ALM 40, Ch. 10 (L. Ji, A. Papadopoulos, S.-T. Yau, eds.) Higher Education Press and International Press, Boston, 2018

Convex real projective orbifolds with radial or totally geodesic ends: a survey of some partial results, Contemp. Math. 696 (2017) 51- 86. arXiv:1601.06952, errata

A classification of radial or totally geodesic ends of real projective orbifolds I: a survey of results, Advanced Studies in Pure Mathematics, 73 (2017) 69-134, MSJ, Tokyo, Japan, arXiv:1501.00348, errata

Topological tameness of Margulis spacetimes, (with William Goldman) American Journal of Mathematics 139 no2. (2017) 297-345, arXiv:1204.5308, mathematica file action2.nb

Projective deformations of weakly orderable hyperbolic Coxeter orbifolds, (with Gye-Seon Lee) Geometry & Topology 19 no.4 (2015) 1777-1828, arXiv:1207.3527

The definability criterion for cocompact convex projective polyhedral reflection groups, (with Kanghyun Choi) Geom. Dedicata 175, no. 1 (2015) 323-346, arXiv:1206.2387

Projective deformations of hyperbolic Coxeter 3-orbifolds, (with Craig D. Hodgson, Gye-Seon Lee) Geom. Dedicata 159 no. 1 (2012) 125-167 aXiv:1003.4352 

Spherical triangles and the two components of the SO(3)-character space of the fundamental group of a closed surface of genus 2, International Journal of Mathematics 22. no. 9(2011) 1261-1364

The maximal tubes under the deformations of a class of 3-dimensional hyperbolic cone-manifolds, (with J. Lee) Siberian Mathematical Journal47 (2006) 955-974

The deformation spaces of projective structures on 3-dimensional Coxeter orbifolds, Geom. Dedicata, 119 (2006) 69-90, addendum

The deformation spaces of convex RP2-structures on 2-orbifolds, (with William Goldman) American Journal of Mathematics 127 (2005) 1019-1122

Geometric structures on low-dimensional manifolds,J. Korean Math. Soc. 40 no.2. (2003) 319--340,  errata.

The decomposition and classification of radiant affine 3-manifolds, Memoirs of Amer. Math. Soc. 730 (2001) 1-122 archive, errata

The universal cover of an affine 3-manifold with holonomy of shrinkable dimension 2 ,  International Journal of Mathematics 11(2000) 305-365, archive

The convex and concave decomposition of manifolds with geometric structures modelled on real projective spaces, Memoires Soc. Math. France, 78 (1999) 1-102, pdf, errata

The classification of real projective structures on surfaces, (with William Goldman) Bull. Amer. Math. Soc. 34 (1997) 161-171.

The Margulis lemma and the thick and thin decomposition for convex real projective surfaces, Advances in Mathematics 122 (1996) 150-191.

Convex decompositions of real projective surfaces I, II, III, Journal of Differential Geometry 40 (1994) 165-208, 239-283, J. Korean Math. Soc. 33 no. 4 (1996) 1139-1171.

Convex real projective structures on closed surfaces are closed, (with William Goldman)  Proc. Amer. Math. Soc. 118 (1993) 657-661.

My mathscinet page

Books

Geometric structures on 2-orbifolds: exploration of discrete symmetry (Math. Soc. of Japan Memoirs, Vol. 27, 2012)

The proceedings of the conference on geometric structures on manifolds, GARC Lecture Note Number 46. in gzipped psfiles.

This is a proceedings of the conference held in 1997 (organized by S. Choi, H. Kim, H. Lee). Writers are Boris Apanasov (U. Oklahoma), Thierry Barbot (ENS-Lyon), Suhyoung Choi (SNU), Christopher Herald (Swarthmore College), Yoshinobu Kamishima (Tokyo Metropolitan University), Sadayoshi Kojima (Tokyo Institute of Technology), Kenichi Ohshika (University of Tokyo), Teruhika Soma (Tokyo Denki University), Myunghee Sung (American University)

Travel

Visiting: UCSB, Univ. Texas, Austin, Florida State University, George Mason University from January 14 to February 14, 2020

Discrete subgroups of Lie groups, Banff International Research Station, Banff, Canada December 8-13, 2019

The dynamics of group actions, in honor of Yves Benoist, Cetraro, Italy, May 27-31, 2019.

Classical and quantum three manifold topology, December 14-21, 2018, Melbourne, Australia

University of Sydney, Sydney, Australia, December 10-13, 2018

The third gear retreat, Stanford University, July 30 - August 12, 2017

JNU-KAIST Geometric Topology Fair, (June 12-16, 2017) Jeju National Univ, South Korea

Differential geometry, and Teichmuller theory, AMS and TIMC, Banaras Hindu University, Varanasi, December 14-17, 2016

Geometry, Topology and Dynamics of Moduli Spaces, NUS, IMA, Singapore, August 1-19, 2016

Geometries, Surfaces and Representations of Fundamental Groups, University of Maryland, College Park, MD, USA, June 22 - 24, 2016

University of Avignon, Avignon, France, February, 22-26, 2016

Differential geometry research group, University of Heidelberg, Heidelberg, Germany, February 8-19, 2016

Geometry of Moduli Spaces of Low Dimensional Manifolds, RIMS, Kyoto, Japan, December 14-18, 2015

Department of Mathematics, Univ. California, Davis, visiting researcher, January 12, 2015 to August 31, 2015

Dynamics on Moduli Spaces of Geometric Structures, a program of MSRI, Berkeley, research member, January 12, 2015 to May 22, 2015

The Ahlfors-Bers Colloquium VI, Yale University, Oct. 23-26, 2014

Hyperbolic Geometry and Geometric Group Theory,  University of Tokyo, July 30-August 5, 2014

What's next? the mathematical legacy of Bill Thurston, Cornell University, June 23-27, 2014

AMS national meeting, Baltimore, MD, January 15-18, 2014 (Univ. Maryland, U. Texas, Austin, U. Texas, Pan American, until the end of January)

Exotic Geometric Structures,  ICERM, Brown University, Providence, RI, September 16-20, 2013

CRM workshop: Higher Teichmüller-Thurston theory, Montreal, October 15-19, 2012

Workshop: Mathematics and Physics of Moduli Spaces, Heidelberg, September 24-28, 2012

 


 

Reviews

AMS mathscinet

I also refereed for American Journal of Mathematics, Proc. Amer. Math. Soc., Journal of Differential Geometry, Geometriae Dedicata, Geometry & Topology, Groups, Geometries, and Dynamics, Duke Mathematical Journal, and so on.