Lettre MODE, Janvier 2026

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1 Bonne année 2026

Chères et chers collègues,

Au nom du groupe SMAI-MODE, je vous adresse mes meilleurs vœux pour cette nouvelle année. Qu’elle soit riche en projets stimulants, en échanges fructueux et en belles réussites, tant sur le plan scientifique que collectif.

Nous espérons avoir le plaisir de vous retrouver nombreux lors des prochaines journées SMAI-MODE de Nice !

Bien cordialement,
Aude Rondepierre

2 Thèses, postdocs et postes

2.1 Professor at ENSTA in Optimisation/proba/ML/Stat

source : Sourour Elloumi
lien : https://enstaparis.recruitee.com/o/enseignant-chercheur-2

We have an opening at ENSTA, at the level of professor.
The general area is optimisation and machine learning. Don’t hesitate to contact us to know more.

2.2 3 offres de thèse à TU Vienne

source : Aris Daniilidis

This PhD project is focused on the optimal control of ordinary differential equations (ODEs). The objective is to identify a control input that minimizes a specific cost functional over a family of system trajectories. The Pontryagin maximum principle establishes necessary conditions for optimality. A central challenge which is a key focus of this project is to analyze the stability of the maximum principle’s results under perturbations of the initial data. The proposed research concerns the investigation of the stability of the mentioned necessary conditions when the time interval where the problem is stated is very long. A typical example is the case when the cost is the (Cesaro) mean of a given function on a time interval [0, T ] and the horizon T tends to infinity. This will be the starting problem of the thesis. Several other interesting ques- tions will be investigated depending on the progress of the PhD student. Beyond the main focus, the project explores two additional areas. First, it investigates optimal control problems involving state constraints, where the regularity of solutions is a little-studied topic. Second, the research extends to non-convex cases; although stability in convex control sets is nowadays well understood, the non-convex situation requires further analysis. The work may also consider connections with Hamilton-Jacobi-Bellman equations. Since the maximum principle is expressed as a generalized equation whose stabil- ity is often analyzed using metric regularity, and considering that the resulting optimization problems are nonsmooth, the PhD candidate will need to under- stand and apply principles of nonsmooth and variational analysis to the field of optimal control.

This research project is part of the French-Austrian International Collaborative Research Project ANR SABOCPR / FWF PIN 4368225. The 3-year doctoral contract will be carried out at the TU Wien, Austria. It is expected that the PhD student spends half of his/her PhD journey at the TU Wien and the other half at the Université de Bretagne Occidentale, Brest, France.

Names and contacts of advisors:
Aris Daniilidis, TU Wien, Austria.
aris.daniilidis@tuwien.ac.at
https://www.arisdaniilidis.at/
Marc Quincampoix, Université de Bretagne Occidentale, LMBA, France.
marc.quincampoix@univ-brest.fr
https://marc.quincampoix.perso.math.cnrs.fr/

This PhD project centers on the study of Hamilton Jacobi Bellman equations, with particular emphasis on the theory of viscosity solutions and infinite-horizon control problems. It also investigates several components of weak KAM theory, including its extension to general metric spaces, as well as abstract notions of descent such as the De Giorgi slope, global slope, and various notions of average slope. A central aim of the project is to develop and clarify the connections between these different frameworks. The proposed research concerns the investigation of appropriate notions of vis- cosity solutions for abstract descent moduli, with special focus on existence, uniqueness and stability of solutions. This corresponds to the starting point of the thesis. Further, and depending on the progresses of the PhD candidate, there are two proposed lines of research. First, due to the fact that the no- tion of viscosity solution was developed to solve Hamilton Jacobi equations, the link between descent moduli and Hamilton-Jacobi equations defined in general metric spaces can be further investigated. Second, connections between the (nonlocal) fractional Laplace equation and global slopes has been investigated. It is interesting to study asymmetric versions of the above operator from both, a PDE and a purely metric viewpoints. Some connections with a nonlocal Tug-of-war game could be also addressed. The main tools to be developed in this project are the ones of viscosity theory to tackle problems from a PDE point of view, and also the ones of variational analysis to deal with problems in the metric case.

This research project is part of the French-Austrian International Collaborative Research Project ANR SABOCPR / FWF PIN 4368225. The 3-year doctoral contract will be carried out at the Université de Rennes, France. It is expected that the PhD student spends the half of his/her PhD journey at the Université de Rennes and the other half at the TU Wien, Austria

Names and contacts of advisors:
Olivier Ley, Univ Rennes, INSA Rennes, IRMAR, France. olivier.ley@insa-rennes.fr
https://ley.perso.math.cnrs.fr/
Aris Daniilidis, TU Wien, Austria.
aris.daniilidis@tuwien.ac.at
https://www.arisdaniilidis.at/

A doctoral fellowship is open in the VADOR group at TU Wien, see https://www.tuwien.at/en/mg/vador/people/vacancies

2.3 Post-Doc in Game Theory and Economic Theory, HEC Paris

source : Marie Laclau

HEC Paris (GREGHEC-CNRS) is hiring a post-doctoral researcher for 2 years, starting anytime between September 2026 and January 2027. This is a postdoc position of CNRS (National Center of Scientific Research), and the candidate will be working at HEC Paris – GREGHEC. They will work mainly on a project financed by an ANR grant on the topic of “Strategic Communication and Costly Signaling” (ANR SCOCOS). The principal investigator of this project is Marie Laclau, researcher at CNRS and associate professor of Economics at HEC Paris. Other members at HEC Paris are Frédéric Koessler and Tristan Tomala. The topic of research is more broadly defined as Economic Theory, Game Theory and Information Economics, with a particular focus on one of the following subjects: (i) signaling games, (ii) dynamic cheap-talk, (iii) dynamic and competitive information design, (iv) strategic communication on networks, (v) information transmission with coarse messages

Applications should be sent to laclau@hec.fr and should include a CV, a motivation letter and two reference letters that should be addressed directly to laclau@hec.fr.

2.4 Séminaires réguliers (dont séminaires en ligne)

N’hésitez pas à signaler un séminaire (avec un lien vers sa page), sa suspension, reprise, etc. par un mail à franck.iutzeler@math.univ-toulouse.fr.

Fin de la lettre MODE

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pour contribuer : envoyer vos contributions à la lettre MODE par mail à l’adresse franck.iutzeler@math.univ-toulouse.fr