On August 31, 2022, Raphael Steiner from the ETH Zürich gave an online at the Virtual Discrete Math Colloquium on the existence of a subdivision of a fixed digraph satisfying constraints on the length of a path replacing each edge in a directed graph of large dichromatic number. The title of his talk was “Congruence-constrained subdivisions in digraphs“.
On August 30, 2022, Jun Gao (高峻) from the IBS Extremal Combinatorics and Probability Group gave a talk at the Discrete Math Seminar about the tight upper bound on the number of (k-1)-cliques in a k-critical graph, solving the conjecture of Abbott and Zhou in 1992. The title of his talk was “Number of (k-1)-cliques in k-critical graph“.
On August 16, 2022, Noleen Köhler from the CNRS, LAMSADE gave a talk at the Discrete Math Seminar on comparing testable properties on graphs of bounded maximum degree and properties expressible by the first-order logic. The title of her talk was “Testing first-order definable properties on bounded degree graphs“. She is currently visiting the IBS Discrete Mathematics Group from August 6 to August 26.
On August 9, 2022, Eun Jung Kim (김은정) from CNRS, LAMSADE, Paris gave a talk at the Discrete Math Seminar on a randomized algorithm for a flow-augmentation in digraphs and its applications for parameterized complexity. The title of her talk was “Directed flow-augmentation”.
On August 3, 2022, Lars Jaffke from the University of Bergen gave an online talk at the Virtual Discrete Math Colloquium on characterizing hereditary graph classes with polynomially many minimal separators. The title of his talk was “Taming graphs with no large creatures and skinny ladders“.
On August 1, 2022, Seunghun Lee (이승훈), who is from the Binghamton University, and will be soon at the Hebrew University of Jerusalem, gave a talk at the Discrete Math Seminar on order types realized by a point configuration whose extreme points are cocircular. The title of his talk was “Inscribable order types“.
The IBS discrete mathematics group welcomes Seokbeom Kim (김석범), a new graduate student at the IBS discrete mathematics group since August 2022. He is currently a graduate student at the department of mathematical sciences, KAIST.