Ben Lund, Maximal 3-wise intersecting families
Room B232 IBS (기초과학연구원)A family
10 events found.
Seminars and Colloquiums
Martin Milanič, Tree Decompositions with Bounded Independence Number
Zoom ID: 869 4632 6610 (ibsdimag)The independence number of a tree decomposition
Jaehoon Kim (김재훈), 2-complexes with unique embeddings in 3-space
Room B232 IBS (기초과학연구원)A well-known theorem of Whitney states that a 3-connected planar graph admits an essentially unique embedding into the 2-sphere. We prove a 3-dimensional analogue: a simply-connected 2-complex every link graph of which is 3-connected admits an essentially unique locally flat embedding into the 3-sphere, if it admits one at all. This can be thought of …
Sebastian Wiederrecht, Matching Minors in Bipartite Graphs
Zoom ID: 869 4632 6610 (ibsdimag)Matching minors are a specialisation of minors which preserves the existence and elementary structural properties of perfect matchings. They were first discovered as part of the study of the Pfaffian recognition problem on bipartite graphs (Polya's Permanent Problem) and acted as a major inspiration for the definition of butterfly minors in digraphs. In this talk …
Casey Tompkins, Ramsey numbers of Boolean lattices
Room B232 IBS (기초과학연구원)The poset Ramsey number
Tuukka Korhonen, Fast FPT-Approximation of Branchwidth
Zoom ID: 869 4632 6610 (ibsdimag)Branchwidth determines how graphs, and more generally, arbitrary connectivity (basically symmetric and submodular) functions could be decomposed into a tree-like structure by specific cuts. We develop a general framework for designing fixed-parameter tractable (FPT) 2-approximation algorithms for branchwidth of connectivity functions. The first ingredient of our framework is combinatorial. We prove a structural theorem establishing …
Seonghyuk Im (임성혁), Large clique subdivisions in graphs without small dense subgraphs
Room B232 IBS (기초과학연구원)What is the largest number
Eun-Kyung Cho (조은경), Independent domination of graphs with bounded maximum degree
Room B232 IBS (기초과학연구원)The independent domination number of a graph
David Munhá Correia, Rainbow matchings
Zoom ID: 869 4632 6610 (ibsdimag)I will discuss various results for rainbow matching problems. In particular, I will introduce a ‘sampling trick’ which can be used to obtain short proofs of old results as well as to solve asymptotically some well known conjectures. This is joint work with Alexey Pokrovskiy and Benny Sudakov.
Tuan Tran, Exponential decay of intersection volume with applications on list-decodability and sphere-covering bounds
Room B232 IBS (기초과학연구원)We give some natural sufficient conditions for balls in a metric space to have small intersection. Roughly speaking, this happens when the metric space is (i) expanding and (ii) well-spread, and (iii) certain random variable on the boundary of a ball has a small tail. As applications, we show that the volume of intersection of …