The IBS Discrete Mathematics Group had its second “DIMAG Internal Workshop” at the St. Johns Hotel of Gangneung on November 15-17, 2021. Participants include almost all current members of DIMAG, Cheolwon Heo from Sungkyunkwan University, and Semin Yoo from KIAS. Every participant presented open problems informally.
Sebastian Wiederrecht gave an online talk on matching minors in biparite graphs at the Virtual Discrete Math Colloquium
On November 11, 2021, Sebastian Wiederrecht from LIRMM gave an online talk at the Virtual Discrete Math Colloquium on building the graph structure theory for matching minors. The title of his talk was “Matching Minors in Bipartite Graphs“.
Jaehoon Kim (김재훈) gave a talk on a sufficient condition for a 2-complex to have a unique embedding in a 3-dimensional space, which is a 3-dimensional analog of Whitney’s theorem on the uniqueness of planar embeddings of a 3-connected graph at the Discrete Math Seminar
On November 9, 2021, Jaehoon Kim (김재훈) from KAIST gave a talk at the Discrete Math Seminar on a 3-dimensional analog of Whitney’s theorem on the uniqueness of planar embeddings of a 3-connected graph. The title of his talk was “2-complexes with unique embeddings in 3-space“.
Martin Milanič gave an online talk on a variation of tree-width of graphs by measuring the width of a tree-decomposition by the size of the largest stable set in a bag at the Virtual Discrete Math Colloquium
On November 5, 2021, Martin Milanič from the University of Primorska, Slovenia gave an online talk at the Virtual Discrete Math Colloquium on a variation of tree-width by measuring the width of a tree-decomposition by the size of the largest stable set in a bag and its algorithmic applications to the maximum weight stable set. The title of his talk was “Tree Decompositions with Bounded Independence Number“.
Ben Lund gave a talk on the smallest size of maximal 3-wise intersecting families of sets at the Discrete Math Seminar
On November 2, 2021, Ben Lund from IBS Discrete Mathematics Group gave a talk on the smallest possible size of a maximal 3-wise intersecting family of subsets of {1,2,…,n} for large n, answering a problem of Erdős and Kleitman proposed in 1974. The title of his talk was “Maximal 3-wise intersecting families“.
Donggyu Kim (김동규) gave a talk on 𝝘-graphic delta-matroids and their algorithmic applications at the Discrete Math Seminar
On October 26, 2021, Donggyu Kim (김동규) from KAIST & IBS Discrete Mathematics Group gave a talk at the Discrete Math Seminar, introducing 𝝘-graphic delta-matroids and showing their algorithmic applications. The title of his talk was “𝝘-graphic delta-matroids and their applications“.
DIMAG had the online workshop “Young Researchers in Extremal and Probabilistic Combinatorics” on October 20-22, 2021.
On October 20-22, 2021, DIMAG had an online workshop “Young Researchers in Extremal and Probabilistic Combinatorics” organized by Tuan Tran and Casey Tompkins. There were 7 invited talks a day for three days.
Invited Speakers & Program
Oct. 20 Wednesday 4 PM (KST) – 8 PM (KST)
- Andrzej Grzesik (Jagiellonian University): Degenerated generalized Turán numbers of cycles, 4:00-4:25
- Jan Volec (Czech Technical University): Existence of common graphs with large chromatic number, 4:30-4:55
- Balázs Patkós (Rényi Institute): Vector sum-intersection theorems, 5:00-5:25
- István Tomon (ETH Zurich): Small doubling, atomic structure and ℓ-divisible set families, 5:30-5:55
- Michael Anastos (Freie Universität Berlin): Longest Cycles in Sparse Random Graphs and Where to Find Them, 6:30-6:55
- Adam Zsolt Wagner (Tel Aviv University): Constructions in combinatorics via neural networks, 7:00-7:25
- Yelena Yuditsky (Université libre de Bruxelles): On multicolor Ramsey numbers and subset-coloring of hypergraphs, 7:30-7:55
Oct. 21 Thursday 4 PM (KST) – 8 PM (KST)
- Kevin Hendrey (IBS Discrete Mathematics Group): Extremal functions for sparse minors, 4:00-4:25
- Simona Boyadzhiyska (Freie Universität Berlin): Ramsey simplicity of random graphs, 4:30-4:55
- Shagnik Das (National Taiwan University): Schur’s Theorem in randomly perturbed sets, 5:00-5:25
- Tony Huynh (Monash University): Subgraph densities in minor-closed classes (and beyond), 5:30-5:55
- Ander Lamaison (Masaryk University): Hypergraphs with minimum uniform Turán density, 6:30-6:55
- Ben Lund (IBS Discrete Mathematics Group): Maximal 3-wise intersecting families, 7:00-7:25
- Liana Yepremyan (London School of Economics): Enumerating independent sets in Abelian Cayley graphs, 7:30-7:55
Oct. 22 Friday 4 PM (KST) – 8 PM (KST)
- Andrey Kupavskii (CNRS): Binary scalar products, 4:00-4:25
- Dániel Gerbner (Rényi Institute): Exact results for generalized Turán problems, 4:30-4:55
- Oliver Janzer (University of Cambridge): Tiling with monochromatic bipartite graphs of bounded maximum degree, 5:00-5:25
- Nika Salia (Rényi Institute): Pósa-type results for Berge Hypergraphs, 5:30-5:55
- Debsoumya Chakraborti (IBS Discrete Mathematics Group): Mixing time and expanders, 6:30-6:55
- Wei-Tian Li (National Chung Hsing University): Ramsey Properties for V-shaped Posets in the Boolean Lattices, 7:00-7:25
- Dimitry Zakharov (Moscow Institute of Physics and Technology): Zero subsums in vector spaces over finite fields, 7:30-7:55
Joonkyung Lee (이준경) gave a talk about the majority dynamics on sparse random graphs at the Discrete Math Seminar
On October 12, 2021, Joonkyung Lee (이준경) from the Hanyang University gave a talk about the majority dynamics on sparse random graphs. The title of his talk was “Majority dynamics on sparse random graphs“.
Paul Seymour gave an online talk on the polynomial 𝜒-boundedness of graph classes at the Virtual Discrete Math Colloquium
On October 8, 2021, Paul Seymour from Princeton University gave an online talk at the Virtual Discrete Math Colloquium on the polynomial 𝜒-boundedness of graph classes. The title of his talk was “Polynomial bounds for chromatic number“.
Eunjin Oh (오은진) gave a talk on a parameterized complexity of the feedback vertex set problem on unit disk graphs at the Discrete Math Seminar
On October 5, 2021, Eunjin Oh (오은진) from POSTECH gave a talk at the Discrete Math Seminar on the parameterized complexity of the feedback vertex set problem on unit disk graphs at the Discrete Math Seminar. The title of her talk was “Feedback Vertex Set on Geometric Intersection Graphs“.