On May 30, 2023, Suyun Jiang (江素云) from Jianghan University gave a talk on the maximum number of edges in a connected graph without a fixed tree at the Discrete Math Seminar. She is currently a visiting scholar at the IBS Extremal Combinatorics and Probability Group. The title of her talk was “How connectivity affects the extremal number of trees.”

## Szymon Toruńczyk gave an online talk, introducing the flip-width of graphs at the Virtual Discrete Math Colloquium

On May 17, 2023, Szymon Toruńczyk from the University of Warsaw gave an online talk at the Virtual Discrete Math Colloquium, introducing the flip-width of graphs at the Virtual Discrete Math Colloquium. The title of his talk was “Flip-width: Cops and Robber on dense graphs.”

## Oliver Janzer gave a talk on finding a subgraph of large average degree on a small vertex set at the Discrete Math Seminar

On May 16, 2023, Oliver Janzer from the University of Cambridge gave a talk at the Discrete Math Seminar on finding a subgraph of large average degree on a small vertex set at the Discrete Math Seminar. The title of his talk was “small subgraphs with large average degree.”

## Maria Chudnovsky gave a colloquium talk on bounding the tree-width by forbidding induced subgraphs

On May 11, 2023, Maria Chudnovsky from Princeton University gave a colloquium talk held at KAIST about bounding the tree-width of graphs by forbidding induced subgraphs. The titlte of her talk was “Induced subgraphs and tree decompositions.”

## Jozef Skokan gave a talk on finding a collection of paths such that for every pair e, f of edges, the collection has a path having e but not f at the Discrete Math Seminar

On May 9, 2023, Jozef Skokan from LSE gave a talk at the Discrete Math Seminar on finding a collection of linearly many paths such that for every pair e, f of distinct edges, there is a path having e but not f in the collection. The title of his talk was “Separating the edges of a graph by a linear number of paths.”

## Rob Morris gave a talk showing the sketch of the proof that the diagonal Ramsey number is less than (4-𝜀)^k at the Discrete Math Seminar

During the Discrete Math Seminar held on May 2, 2023, Rob Morris of IMPA presented on the recent breakthrough regarding the diagonal Ramsey number, specifically demonstrating that $R(k,k)<(4-\varepsilon)^k$. The title of his talk was “An exponential improvement for diagonal Ramsey.”

## Rob Morris gave a colloquium talk at KAIST on Ramsey Theory

On April 27, 2023, Rob Morris from IMPA gave a colloquium talk on Ramsey Theory at the Colloquium of KAIST Mathematical Sciences. The title of his talk was “Ramsey theory: searching for order in chaos.” Rob Morris is currently visiting IBS and will give a seminar talk at IBS on May 2 with more details on his latest theorem on diagonal Ramsey numbers.

## Hyunwoo Lee (이현우) gave a talk on partitioning a graph into induced subgraphs each having a subdivision of a fixed graph as a subgraph at the Discrete Math Seminar

On April 25, 2023, Hyunwoo Lee (이현우) from KAIST and IBS Extremal Combinatorics and Probability Group gave a talk at the Discrete Math Seminar about the minimum degree condition to have a partition of a graph into induced subgraphs each having a subdivision of a fixed graph as a subgraph. The title of his talk was “On perfect subdivision tilings.”

## James Davies gave a talk on the 𝜒-boundedness and the strong Erdős-Hajnal property of proper pivot-minor-closed classes of graphs at the Discrete Math Seminar

On April 11, 2023, James Davies from the University of Cambridge gave a talk at the Discrete Math Seminar on his two theorems stating that proper pivot-minor-closed classes of graphs are 𝜒-bounded and have the strong Erdős-Hajnal property. The title of his talk is “two structural results for pivot-minors.”

## István Tomon gave a talk on the intersection graph of axis-parallel boxes at the Discrete Math Seminar

On April 4, 2023, István Tomon from Umeå universitet, Sweden gave a talk at the Discrete Math Seminar on the intersection graph of axis-parallel boxes at the Discrete Math Seminar. The title of his talk was “Configurations of boxes.”