Schedule and Abstracts 2025/2026

If not stated otherwise, the talk will take place Wednesdays starting at 4:15pm in A3/SR 119
Date Speaker Title
14.01.2026
4:15 pm
A3, SR120
Felix Clemen (University of Victoria) Regular Simplices in Higher Dimensions
08.01.2026 Michael Zheng (Emory University) A Lovász-Kneser theorem for triangulations

Abstracts

14.01.2026
Felix Clemen (University of Victoria)
Regular Simplices in Higher Dimensions
Abstract: A classical problem in combinatorial geometry, posed by Erdős in 1946, asks to determine the maximum number of unit segments in a set of \(n\) points in the plane. Since then a great variety of extremal problems in finite point sets have been studied. Here, we look at generalizations of this question concerning regular simplices. Among others we answer the following question asked by Erdős: Given \(n\) points in \(\mathbb{R}^6\), how many triangles can be equilateral triangles? For our proofs we use hypergraph Turán theory and linear algebra. This is joint work with Dumitrescu and Liu.
08.01.2026
Michael Zheng (Emory University)
A Lovász-Kneser theorem for triangulations
Abstract: We show that the Kneser graph of triangulations of a convex n-gon has chromatic number \(n - 2\). Joint work with Anton Molnar, Cosmin Pohoata, and Daniel G. Zhu

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