기초과학연구원 이산수학그룹
On June 17, 2025, Attila Jung from the Eötvös Loránd University, Hungary gave a talk at the Discrete Math Seminar on combining the fractional Helly theorem and the quantitative volume theorem on convex sets optimally. The title of his talk was “The Quantitative Fractional Helly Theorem“.
On June 10, 2025, On-Hei Solomon Lo from Tongji University in Shanghai gave a talk at the Discrete Math Seminar on characterizing minor-minimal 3-connected non-Hamiltonian graphs. The title of his talk was “Minors of non-hamiltonian graphs“.
On June 4, 2025, Denys Bulavka from the Hebrew University of Jerusalem gave a talk at the Discrete Math Seminar on the maximum size of intersecting families of k-element facets in simplicial complexes. The title of his talk was “Strict Erdős-Ko-Rado Theorems for Simplicial Complexes“.
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“.
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“.