Lasserre-type hierarchies in discrete geometry

par Nando Leijenhorst

jeudi 27 nov. 2025, 16:00 → 17:00 Europe/Paris

1R2 - 207 (Salle Pellos) (IMT)

In discrete geometry, we study configurations of points under certain conditions. We are mostly interested in extremal configurations: What is the densest packing of spheres in R^n? What is the minimum number of spherical caps of a certain size needed to cover a unit sphere?

One approach to such problems is to generalize the moment-SOS techniques from polynomial optimization. 

In this talk, I'll discuss these techniques and their generalization to the problem of finding the maximum size of a spherical code, including an example where the bounds are exact, which gives conditions on the optimal configuration(s).