기초과학연구원 이산수학그룹
On May 27, 2025, Meike Hatzel from the IBS Discrete Mathematics Group gave a talk at the Discrete Math Seminar on the existence of a graph of arbitrary large girth and chromatic number admitting a proper edge coloring without a color appearing alone in any cycle. The title of her talk was “Counterexample to Babai’s lonely colour conjecture“.
On May 13, 2025, Seokbeom Kim (김석범) from KAIST and the IBS Discrete Mathematics Group gave a talk on the structure of tournaments without a fixed 5-vertex tournament and its applications to the dichromatic number at the Discrete Math Seminar. The title of his talk was “The structure of △(1, 2, 2)-free tournaments“.
The IBS Discrete Mathematics Group welcomes Sarah Wajsbrot, a new graduate student of the Discrete Mathematics Group from May 6, 2025 until July 5, 2025. She is a Ph.D. student in computer science at Université de Lorraine. Her advisor is Xavier Goaoc.
The IBS discrete mathematics group welcomes Dr. Roohani Sharma, a new research fellow at the IBS Discrete Mathematics Group from May 1, 2025. She received her Ph.D. from the Institute of Mathematical Sciences, Chennai, India, under the supervision of Prof. Saket Saurabh. She is interested in parameterized complexity and kernelization. Previously, she was a researcher at the University of Bergen, Norway, and a Lise-Meitner Post-doctoral Fellow at the Max Planck Institute for Informatics in Germany.
The IBS Discrete Mathematics Group welcomes Ho Kim (김호), a new graduate student of the Discrete Mathematics Group from May 1, 2025. He received his B.S. degree from Hanyang University and entered the Department of Mathematical Sciences at KAIST as a graduate student on September 2024. His advisor is Jaehoon Kim (김재훈).
On April 29, 2025, Eunjin Oh (오은진) from POSTECH gave a talk at the Discrete Math Seminar on an almost linear-time approximation algorithm for the minimum-weight b-edge cover on geometric complete bipartite graphs. The title of her talk was “Approximation Algorithms for the Geometric Multimatching Problem“.
On April 28, 2025, Pascal Schweitzer from the Technical University of Darmstadt gave a talk on finding symmetries and deciding isomorphic graphs at the Discrete Math Seminar. The title of his talk was “Recent insights surrounding combinatorial approaches to isomorphism and symmetry problems“.
On April 22, 2025, Marcin Briański from Jagiellonian University in Krakóv, Poland gave a talk on the existence of large Burling graphs or large complete graphs on string graphs of very large chromatic number at the Discrete Math Seminar. The title of his talk was “Burling Graphs as (almost) universal obstacles to 𝜒-boundedness“.
On April 15, 2025, Nicola Lorenz from the University of Hamburg gave a talk on the existence of a normal tree spanning a given set of vertices in an infinite graph in terms of the coloring number of rooted minors at the Discrete Math Seminar. The title of her talk was “A Minor Characterisation of Normally Spanned Sets of Vertices“.
On April 14, 2025, Daniel McGinnis from Princeton University gave a talk on determining the existence of a k-dimensional affine subspace intersecting every member of a given finite family of convex sets in the d-dimensional real space at the Discrete Math Seminar. The title of his talk was “A necessary and sufficient condition for k-transversals“.