Nom de l'auteur
Vandanjon
Prénom de l'auteur
Hanaë
Date de soutenance
Nom du ou des directeurs de thèse
Bénéa
Bernicot

L'objet de cette thèse est d'étudier et de développer l'analyse temps-fréquence pour des multiplicateurs de Fourier présentant une singularité de type "transformée de Hilbert bilinéaire" (avec des singularités dans des directions dégénérées, des shifts, ...).

Etablissement d'origine
Nantes université

comment

Yuichi Ike
Etablissement de l'orateur
University of Tokyo
Date et heure de l'exposé
Lieu de l'exposé
salle des séminaires
Résumé de l'exposé

In this talk, we show that if the image of an embedded Legendrian in a cosphere bundle under a contact homeomorphism is smooth, then it remains Legendrian and its Maslov class is preserved. Our proof is based on the microlocal sheaf theory, using the continuity of the interleaving distance of sheaves with respect to the C0-distance. This is joint work in preparation with Tomohiro Asano, Christopher Kuo, and Wenyuan Li.

type actualité

Soutenances des masters Ingénierie statistique

Date de début de l'actualité
03-09-2025 09:30
Date de fin de l'actualité
04-09-2025 17:00

Les soutenances de stage des M2 IS se dérouleront les mercredi 3 et jeudi 4 septembre prochains.

type actualité

Séminaire quimpériodique

Date de début de l'actualité
09-10-2025 09:00
Date de fin de l'actualité
10-10-2025 17:00

Le prochain séminaire quimpériodique aura lieu les 9 et 10 octobre prochain. Les inscriptions sont déjà ouvertes ici : https://www.lebesgue.fr/fr/QMPoctobre2025/inscription

Bingyu Zhang
Etablissement de l'orateur
University of Southern Denmark
Date et heure de l'exposé
Lieu de l'exposé
salle Éole
Résumé de l'exposé

In this talk, I will explain how to relate the Novikov ring and microlocal sheaf theory based on the works of Tamarkin and Vaintrob. This relation has been successfully applied to the irregular Riemann-Hilbert correspondence and symplectic geometry, and recently, Scholze revealed certain potential applications of the relation in analytic geometry. Surprisingly, we notice that the almost ring theory invented by Faltings for p-adic Hodge theory plays a central role in the related construction. After that, I will explain some applications of the idea in symplectic geometry.

This talk is based on a joint work with Tatsuki Kuwagaki.

Matthieu MÉNARD
Etablissement de l'orateur
Université Paris Cité
Date et heure de l'exposé
Lieu de l'exposé
Salle des séminaires
Résumé de l'exposé

We consider a system of N Brownian particles interacting through a long-range smooth potential. It is known that "propagation of chaos" holds in the mean-field scaling. Assume indeed that the initial distribution of the particles is chaotic, i.e. that the particles are independent and identically distributed. Then, for any given time, and as N becomes large, the distribution of particles remains chaotic. Moreover, the distribution of a typical particle is given by the solution of a Vlasov-Fokker-Planck equation.

In this talk, we will investigate the creation of chaos phenomenon. Starting from an initial distribution of particles which is only exchangeable, we prove that in some weak norm, propagation of chaos holds up to an error stemming from initial correlations, exponentially damped over time. This is a joint work with Armand Bernou and Mitia Duerinckx.

Soumyajit SAHA
Etablissement de l'orateur
IRMA (Strasbourg)
Date et heure de l'exposé
Lieu de l'exposé
Résumé de l'exposé

In this talk, we discuss the effects of perturbations on the topology and geometry of nodal sets/zero sets of Laplace eigenfunctions. A conjecture by Payne states that the nodal set of the second Dirichlet eigenfunction on a bounded planar domain intersects the boundary at exactly two points. We will look into certain stability properties of the nodal sets and discuss some recent results concerning the conjecture. Then, utilising the stability properties, we will observe the prescription of nodal data on Riemannian surfaces, focusing on the following two aspects: the construction of eigenfunctions with a prescribed number of nodal intersections at the boundary, and the realisation of Courant-sharp eigenfunctions at arbitrarily high levels.

comments

Contact pour l'enseignement
Gabriel Rivière
Date d'embauche
date de début de Période de publicité
date de fin de période de publicité
Description de l'emploi

Applicants must have obtained a Ph.D. or equivalent degree before starting the postdoc position and should be within 3 years after their PhD defense when starting the postdoc position. The successful applicant must have strong background in one or several of the following topics related to this project: spectral theory, microlocal or semiclassical analysis, dynamical systems, probability, mathematical quantum chaos. Moreover some experience in sub-Riemannian geometry will be most appreciated. In particular, the goal of this short term position is to study an approximation scheme that is taylored to a general sub-Riemannian structure and we aim for instance at describing joint asymptotic expansions for the heat kernel. He/She will have facilities to travel and he/she will be able to interact with members of the research project throughout France.

Poste pourvu
NON