Conférence
Notice
Langue :
Anglais
Crédits
Fanny Bastien (Réalisation), Donovan HUMPHRIES (Réalisation), André Ricardo Belotto Da Silva (Intervention)
Conditions d'utilisation
CC BY-NC-ND 4.0
DOI : 10.60527/snyq-ex19
Citer cette ressource :
André Ricardo Belotto Da Silva. I_Fourier. (2019, 5 juillet). A. Belotto da Silva - Singular foliations in sub-Riemannian geometry and the Strong Sard Conjecture , in 2019. [Vidéo]. Canal-U. https://doi.org/10.60527/snyq-ex19. (Consultée le 19 mars 2024)

A. Belotto da Silva - Singular foliations in sub-Riemannian geometry and the Strong Sard Conjecture

Réalisation : 5 juillet 2019 - Mise en ligne : 30 août 2019
  • document 1 document 2 document 3
  • niveau 1 niveau 2 niveau 3
Descriptif

Given a totally nonholonomic distribution of rank two $\Delta$ on a three-dimensional manifold $M$, it is natural to investigate the size of the set of points $\mathcal{X}^x$ that can be reached by singular horizontal paths starting from a same point $x \in M$. In this setting, the Sard conjecture states that $\mathcal{X}^x$ should be a subset of the so-called Martinet surface of 2-dimensional Hausdorff measure zero.

I will present a reformulation of the conjecture in terms of the behavior of a (real) singular foliation. Next, I will present a recent work in collaboration with A. Figalli, L. Rifford and A. Parusinski, where we show that the (strong version of the) conjecture holds in the analytic category and in dimension 3. Our methods rely on resolution of singularities of surfaces, foliations and metrics; regularity analysis of Poincaré transition maps; and on a simpletic argument, concerning a transversal metric of an isotropic singular foliation.

Intervention

Dans la même collection

Sur le même thème