Séminaire Francilien de Géométrie Algorithmique et Combinatoire

Le Séminaire de Géométrie Algorithmique et Combinatoire vise à regrouper des exposés dans ce domaine au sens le plus large, et dans les disciplines connexes en mathématiques et informatique. Il est ouvert à tous les chercheurs et étudiants intéressés. Les exposés sont destinés à un public large.

On reprend les activités en presentiel un jeudi tous les deux mois à 14h, à l'IHP, en salle 421.

Pour recevoir les annonces de ce séminaire, envoyer un message à arnaud [dot-sign] de-mesmay [the-funny-at-sign] univ-eiffel [dot-sign] fr

La liste des exposés passés est disponible ici.


15 décembre 2022
14h Adrian Vladu IRIF, CNRS
Discrepancy Minimization via Regularization
We introduce a new algorithmic framework for discrepancy minimization based on regularization. We demonstrate how varying the regularizer allows us to re-interpret several breakthrough works in algorithmic discrepancy, ranging from Spencer's theorem to Banaszczyk's bound. Using our techniques, we also show that the Beck-Fiala and Komlos conjectures are true for a new regime of pseudorandom instances. Joint work with Lucas Pesenti (SODA 2023), paper: https://arxiv.org/abs/2211.05509
15h30 Bruno Vallette Université Sorbonne Paris Nord
Graphs in the operadic calculus
In order to encode algebraically the intricate combinatorics of all the higher operations of homotopy algebras, topologists introduced in the 70’s the fundamental notion of an operad. This notion enjoyed a profound renaissance outside topology in the mid 90’s when it was noticed that this universal notion could be applied as well in algebra (Koszul duality), geometry (moduli spaces of curves, Gromov—Witten invariants), and mathematical physics (mirror symmetry conjecture). Over the past 30 years, an operadic calculus has been extensively developed and applied successfully in many domains. In this talk, I would like to survey the various types of graphs lying at the core of the theory of operads including their combinatorial properties since they are the main arguments of many proofs.

Le séminaire bénéficie du soutien de l'Institut Henri Poincaré.

Le comité d'organisation est constitué de Alfredo Hubard, Arnaud de Mesmay et Lionel Pournin.