Luke Postle, Further progress towards Hadwiger’s conjecture

Zoom ID: 869 4632 6610 (ibsdimag)

In 1943, Hadwiger conjectured that every graph with no $K_t$ minor is $(t-1)$-colorable for every $t\ge 1$. In the 1980s, Kostochka and Thomason independently proved that every graph with no $K_t$ minor has average degree $O(t\sqrt{\log t})$ and hence is $O(t\sqrt{\log t})$-colorable.  Recently, Norin, Song and I showed that every graph with no $K_t$ minor is

Zihan Tan, Towards Tight(er) Bounds for the Excluded Grid Theorem

Zoom ID: 869 4632 6610 (ibsdimag)

We study the Excluded Grid Theorem, a fundamental structural result in graph theory, that was proved by Robertson and Seymour in their seminal work on graph minors. The theorem states that there is a function $f$, such that for every integer $g > 0$, every graph of treewidth at least $f(g)$ contains the g×g-grid as a minor. For every

Minki Kim (김민기), Complexes of graphs with bounded independence number

Room B232 IBS (기초과학연구원)

Let $G$ be a graph on $V$ and $n$ a positive integer. Let $I_n(G)$ be the abstract simplicial complex whose faces are the subsets of $V$ that do not contain an independent set of size $n$ in $G$. We study the collapsibility numbers of $I_n(G)$ for various classes of graphs, focusing on the class of

Livestream

Hong Liu (刘鸿), Cycles and trees in graphs (1/8)

Zoom ID:8628398170 (123450)

This lecture series covers several different techniques on embedding paths/trees/cycles in (pseudo)random graphs/expanders as (induced) subgraphs.

Livestream

Hong Liu (刘鸿), Cycles and trees in graphs (2/8)

Zoom ID:8628398170 (123450)

This lecture series covers several different techniques on embedding paths/trees/cycles in (pseudo)random graphs/expanders as (induced) subgraphs.

Livestream

Hong Liu (刘鸿), Cycles and trees in graphs (3/8)

Zoom ID:8628398170 (123450)

This lecture series covers several different techniques on embedding paths/trees/cycles in (pseudo)random graphs/expanders as (induced) subgraphs.

Livestream

Hong Liu (刘鸿), Cycles and trees in graphs (4/8)

Zoom ID:8628398170 (123450)

This lecture series covers several different techniques on embedding paths/trees/cycles in (pseudo)random graphs/expanders as (induced) subgraphs.

Livestream

Hong Liu (刘鸿), Cycles and trees in graphs (5/8)

Zoom ID:8628398170 (123450)

This lecture series covers several different techniques on embedding paths/trees/cycles in (pseudo)random graphs/expanders as (induced) subgraphs.

Livestream

Hong Liu (刘鸿), Cycles and trees in graphs (6/8)

Zoom ID:8628398170 (123450)

This lecture series covers several different techniques on embedding paths/trees/cycles in (pseudo)random graphs/expanders as (induced) subgraphs.

IBS 이산수학그룹 Discrete Mathematics Group
기초과학연구원 수리및계산과학연구단 이산수학그룹
대전 유성구 엑스포로 55 (우) 34126
IBS Discrete Mathematics Group (DIMAG)
Institute for Basic Science (IBS)
55 Expo-ro Yuseong-gu Daejeon 34126 South Korea
E-mail: dimag@ibs.re.kr, Fax: +82-42-878-9209
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