Embedding graphs and digraphs

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Yuval Wigderson, ETH Zurich
Fine Hall 224

Many fundamental questions and results in graph theory, from Dirac's and Turán's theorems to the Erdős–Hajnal and Gyárfás–Sumner conjectures, can be phrased as graph embedding problems: showing that a certain graph can be embedded into any other graph satisfying certain natural properties. Over the past decades, a number of powerful techniques have been developed to address such problems.

In this talk, I will focus on one such technique, the dependent random choice method. I will discuss some new variations on this technique, and show how they can be used to resolve a number of embedding questions about graphs and digraphs, such as a "higher-dimensional" generalization of Rédei's theorem on Hamiltonian paths in tournaments.

Based on joint works with Zach Hunter, António Girão, and Patryk Morawski.