On December 9, 2020, Karl Heuer from Technische Universität Berlin gave an online talk on the problem of detecting even directed circuits in a regular oriented matroid and related classes of oriented matroids at the Virtual Discrete Math Colloquium. The title of his talk was “Even Circuits in Oriented Matroids“.
Hong Liu presented his result with R. Montgomery on the resolution the odd cycle problem of Erdős and Hajnal at the Discrete Math Seminar
On December 8, 2020, Hong Liu from University of Warwick presented a talk on his recent work with Richard Montgomery, answering the odd cycle problem of Erdős and Hajnal (1981). The title of his talk is “A solution to Erdős and Hajnal’s odd cycle problem“.
Deniz Sarikaya presented results on necessary conditions for locally finite graphs to have a Hamiltonian cycle at the Virtual Discrete Math Colloquium
On December 3, 2020, Deniz Sarikaya from Universität Hamburg gave an online talk about necessary conditions for locally finite graphs to have a Hamiltonian cycle in terms of their forbidden induced subgraphs. The title of his talk was “What means Hamiltonicity for infinite graphs and how to force it via forbidden induced subgraphs“.
Joonkyung Lee (이준경) gave online talks on the Ramsey multiplicity and common graphs at the Discrete Math Seminar
On November 30 and December 2, 2020, Joonkyung Lee (이준경) from University College London gave two online talks on the Ramsey multiplicity and common graphs at the Discrete Math Seminar organized by Jaehoon Kim at KAIST. The titles of his talks are “On Ramsey multiplicity” and “On common graphs“.
(The photo above was taken earlier in his other seminar talk.)
Debsoumya Chakraborti gave a talk on finding a rainbow matching in an edge-colored graph at the Discrete Math Seminar
On December 1, 2020, Debsoumya Chakraborti from the IBS Discrete Mathematics Group presented his theorem with Po-Shen Loh about the existence of a rainbow matching of size q in a simple graph whose edges are colored properly by 2q+o(q) colors. The title of his talk was “Rainbow matchings in edge-colored simple graphs“.
Duksang Lee presented his work on the characterization of delta-graphic matroids at the Discrete Math Seminar
On November 24, 2020, Duksang Lee (이덕상) from KAIST and the IBS Discrete Mathematics Group gave a talk on the characterization of matroids whose bases form graphic delta-matroids at the Discrete Math Seminar. The title of his talk was “Characterizing matroids whose bases form graphic delta-matroids“.
Yijia Chen gave an online talk on the shrub-depth of graph classes at the Virtual Discrete Math Colloquium
On November 19, 2020, Yijia Chen (陈翌佳) from Fudan University spoke at the Virtual Discrete Math Colloquium on the shrub-depth of graph classes. The title of his talk is “Graphs of bounded shrub-depth, through a logic lens“.
Meike Hatzel gave a talk on finding a bramble of small order and small size at the Virtual Discrete Math Colloquium
On November 11, 2020, Meike Hatzel from Technische Universität Berlin gave an online talk on the existence of a bramble of small order and small size in a graph of tree-width k at the Virtual Discrete Math Colloquium. The title of her talk was “Constant congestion bramble“.
Casey Tompkins gave a talk on extremal problems on Boolean and linear lattices with forbidden posets at the Discrete Math Seminar
On November 10, 2020, Casey Tompkins from the IBS Discrete Mathematics Group presented a talk on the extremal problems on Boolean and linear lattices with forbidden posets at the Discrete Math Seminar. The title of his talk was “Extremal forbidden poset problems in Boolean and linear lattices“.
Daniel Cranston gave a talk on partitioning the vertex set of a graph into an edge-less graph and a forest consisting of small components at the Virtual Discrete Math Colloquium
On November 5, 2020, Daniel Cranston from Virginia Commonwealth University gave a talk on the condition of the maximum average degree for a graph to have a partition of its vertex set into an independent set and a set inducing a forest consisting of components of small size at the Virtual Discrete Math Colloquium. The title of his talk was “Vertex Partitions into an Independent Set and a Forest with Each Component Small“.











