LPTMS PhD Proposal: Phase transition in Mean Field Games

Responsable: Denis ULLMO 01 69 15 74 76

Mean field games present a new area of research at the boundary between applied mathematics, social sciences, engineering sciences and physics. It has been initiated a decade ago by Pierre-Louis Lions (recipient of the 94 Fields medal) and Jean-Michel Lasry as a new and promising tool to study many problem of social sciences, and with an explicit mention of the influence of concepts coming from physics (the notion of “mean field approximation”). This field has since then grown significantly, and after a period where mainly stylized models where introduced, we witness now the appearance of (necessarily more involved) mean field game models closer to practical applications in finance, vaccination policies, or energy management through smart electronics. Up to now, the development of Mean Field Games has mainly originated from the mathematics and economic communities. Mean Field Games theory is, however, by essence a multi-disciplinary field for which the input of physicists is much needed. Indeed, as important as they are, the studies of internal consistency and the numerical schemes developed by mathematicians cannot replace the deeper understanding of the behavior of these models, obtained in particular through powerful approximation schemes, that physicists (and essentially only them) know how to provide.

In this general context, the goal of this internship will be to study "phase transitions" in MFG, that is a discontinuous changes of behavior as a parameter is varied.  During the internship, this study will be limited to a class of Mean Field Games for which there exist a formal, but deep, connection with the non-linear Schrödinger equation, which is making their analysis, and in particular the origin of these phase transitions, more transparent.


LPTMS Postdoc: Postdoctoral position in low-dimensional quantum systems (theory), 2 years funded

The position is funded as a part of an Austrian-French research collaboration aimed at exploring, in a joint experimental and theoretical effort, the dynamics of impurities inside quantum wires of ultracold atoms. Dr. Mikhail Zvonarev and Prof. H.C. Naegerl coordinate the project on the French and Austrian sides, respectively. The successful applicant will work at the Laboratory of Theoretical Physics and Statistical Models (LPTMS), Orsay, France. A solid background of the applicant in theoretical quantum condensed matter physics is necessary, an experience in the analytical/numerical approaches to low dimensional systems is desirable.

 

Application should be prepared as a single PDF file containing

  • Letter of motivation (max. half a page)

  • CV + List of publications

  • Contact details of at least two possible referees

     

It should be sent by e-mail to mikhail.zvonarev@gmail.com,

subject line Postdoc_Your Family Name

There is no deadline for the application, the search will continue until the position is filled.


LPTMS PhD Proposal: Emergence of fibers in frustrated self-assembly

Responsable: Martin Lenz 01 69 15 32 62

Self-organization is key to the function of living cells – but sometimes goes wrong! In Alzheimer’s
and many other diseases, normally soluble proteins thus clump up into pathological fiber-like
aggregates. While biologists typically explain this on the grounds of detailed molecular interactions, we
have started proving that such fibers are actually expected from very general physical principles. We
thus show that geometrical frustration builds up when mismatched objects self-assemble, and
leads to non-trivial aggregate morphologies, including fibers.

Despite several examples of this in our numerical simulations (see illustration), we have yet to
better understand the underlying physics. Is fiber formation based on a well-defined phase transition? Is
this transition fundamentally out of equilibrium as some of our results suggest? To what extent can it be
mapped onto the standard geometrical understanding of frustration as the embedding of a manifold into
a space with an incompatible metric? We will tackle these questions using two minimal models of
frustration where we hope to combine analytical and numerical insights. One of these is akin to
historical descriptions of Josephson junctions, where lattice-based Heisenberg spins want to realize a
certain fixed mismatch in their alignments between neighboring sites.

This project offers opportunities for collaborations with the theoretical group of Gregory Grason at
U. Mass. Amherst (USA), as well as with several groups that are currently initiating experiments on
frustration-driven fiber formation.

Informal inquiries welcome.

pdf


LPTMS Poste: Maître de Conférences 2018 / Assistant professor position

English version of this context below the French one

Physique et modélisation statistique : aspects classiques et quantiques

Un poste de maître de conférences devrait être proposé au concours au printemps 2018.

Enseignement

Le ou la candidate devra être à même d'enseigner à tous les niveaux de la formation universitaire. Elle ou il pourra dispenser un enseignement général en licence (en physique ou dans les disciplines connexes comme les mathématiques, l'informatique, voire la biologie ou la chimie). Plus spécifiquement, des besoins urgents se profilent avec l'arrivée de l'Ens Paris-Saclay, ainsi qu'avec la montée en puissance des double diplômes comme la Licence Mathématiques Physique. Enfin, la future recrue sera amenée à s'investir au sein du Master des Systèmes Complexes, qui est actuellement en restructuration profonde. Une expérience d'enseignement, acquise en thèse ou pendant des années postdoctorales, est souhaitable.

Recherche

Le LPTMS souhaite développer son activité dans les applications de la physique statistique, en matière condensée au sens large, mais également en direction d'un certain nombre d'interfaces qui sont explorées actuellement (mathématiques, chimie, théorie de l'information, biologie,…). Le profil recherché est celui d'une candidature avec une excellente formation en physique théorique, capable d'interagir avec une ou plusieurs des équipes du LPTMS. Une bonne connaissance de la physique numérique sera un atout.

Contexte

Ce recrutement s'insère au sein du Centre de Physique Matière et Rayonnement (CPMR) de la future Université Paris-Saclay (regroupement de 5 laboratoires LPS-LAC-FAST-ISMO-LPTMS), et un intérêt pour les applications de la théorie aux problèmes expérimentaux sera apprécié. Le déménagement du LPTMS en novembre 2018, au coeur même du CPMR, est de ce point de vue un atout important.

Attention, les candidats doivent être qualifiés par le CNU pour pouvoir candidater. La date limite pour initier les démarches de qualification est le 24 octobre 2017, consulter

https://www.galaxie.enseignementsup-recherche.gouv.fr/ensup/cand_qualification_droit_commun.htm

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Statistical Physics and Modelling : classical and quantum aspects

An assistant professor position will presumably be open in 2018, with competition taking place during the spring.

Teaching

The candidate will teach at all University levels. He/She will take part in the undergraduate physics program, and possibly in other programs such as mathematics, informatics, or biology and chemistry. More specifically, the settlement of Ens Paris-Saclay on campus and the rise of mixed mathematics-physics curricula go with enhanced needs of physics teaching. In addition, the selected person will have the opportunity to get involved into the newly reorganized Physics of Complex Systems Masters. A significant experience in teaching during doctoral and/or post-doctoral studies will be appreciated.

Research activities

LPTMS aims at developing its activities, from applications of statistical physics in condensed matter physics in a broad sense, to new directions that are currently being investigated at the interface with mathematics, chemistry, information theory or biology. The candidate is expected to have a strong background in theoretical physics, and to be able to interact with one or several teams at LPTMS. A good knowledge of computational physics will be an advantage. The position will integrate the future Centre de Physique Matière et Rayonnement (CPMR) of the Paris-Saclay University, a joint program of 5 laboratories LPS-LAC-FAST-ISMO-LPTMS. The relocation of LPTMS within the premises of CPMR in November 2018 is an important perspective and an interest in experimental questions will thus be appreciated.

Candidates are expected to have a good command of French language. Besides, they should be beforehand qualified by the CNU. The deadline to initiate the qualification procedure is Oct 24 2017, see

https://www.galaxie.enseignementsup-recherche.gouv.fr/ensup/cand_qualification_droit_commun.htm


LPTMS Postdoc: Condensed Matter Theory

A two-year postdoctoral position in statistical physics and condensed matter theory is available at LPTMS, a joint laboratory of CNRS and University Paris-Saclay, starting in the fall of 2018. The candidate is expected to study the interplay of thermalization and many-body localization in open quantum systems out of equilibrium in collaboration with A. Rosso. The candidate should have good background in statistical/condensed matter physics.

This position is financed by the ANR grant "Thermalization and Localization in quantum systems" and will include strong collaborations with D. Basko and M. Holzmann (LPMMC, Grenoble). Collaborations with F. Alet and N. Laflorencie (LPT, Toulouse) are also encouraged. Depending on the project and the candidate's expertise and preferences, the work might range from mostly analytical to largely numerical.

Applications including a CV, a list of publications, a brief description of past research and future interests should be sent to Claudine Le Vaou by email at secretariat.lptms@lptms.u-psud.fr. Applicants should also arrange for three letters of recommendation to be sent to the same address. Informal inquiries are welcome. Review of applications will begin on November 1st 2017 and continue until the position is filled.

Contact:
Alberto Rosso
http://lptms.u-psud.fr/alberto_rosso/