Le contenu scientifique de cette journée sera tourné vers la géométrie arithmétique, la géométrie algébrique et la géométrie analytique ainsi que la topologie algébrique.L’inscription est gratuite et ouverte jusqu’au 25 janvier 2024.Organisateur : Dustin Clausen (IHES)Conférenciers invités :Arthur-César Le Bras (CNRS, Université de Strasbourg)Vincent Pilloni (CNRS, Université Paris-Saclay)Tomer Schlank (Hebrew University of Jerusalem)Peter Scholze (MPIM Bonn) 

Arithmetic GeometryApril 22-26, 2024at IHES – Centre de conférence Marilyn et James SimonsOn the occasion of Hélène Esnault’s 70th birthday, Marco D’Addezio, IRMA Strasbourg, Kay Rülling, Univ. Wuppertal, and Tanya Srivastava, IIT Gandhinagar, organize a conference in her honor from April 22 to 26, 2024.This conference centers around the mathematical contributions and interests of Hélène Esnault. It aims at bringing together mathematicians with diverse backgrounds, providing a platform to exchange their ideas and foster new collaborations. Registration deadline: January 31, 2024Invited Speakers:Tomoyuki Abe, IPMU – University of Tokyo  Yves André, IMJ-PRG  Emelie Arvidsson, University of UtahBhargav Bhatt, IAS – Princeton University & University of Michigan  Ana Caraiani, Imperial College London  Dustin Clausen, IHES Johan De Jong, Columbia University  Michael Groechenig, University of Toronto  Lars Hesselholt, Nagoya University & University of Copenhagen Katharina Hübner, Goethe-Universität Frankfurt  Moritz Kerz, Universität Regensburg      Marc Levine, Universität Duisburg-Essen  Daniel Litt, University of Toronto   Alexander Petrov, Harvard University  Claude Sabbah, École polytechnique  Peter Scholze, MPIM – University of Bonn   Atsushi Shiho, University of Tokyo  Carlos Simpson, Université Nice-Sophia AntipolisVasudevan Srinivas, SUNY, BuffaloJakob Stix, Goethe-Universität Frankfurt  Scientific Committee: Marco D’Addezio (IRMA Strasbourg), Marcin Lara (Goethe Universität-Frankfurt), Simon Pépin Lehalleur (Radboud Universiteit Nijmegen), Kay Rülling (Universität Wuppertal), Annette Werner (Goethe Universität-Frankfurt), and Lei Zhang (Sun Ya-Tsen Univ. Zhuhai) Hélène Esnault is a mathematician specializing in algebraic and arithmetic geometry. She obtained her PhD in 1976 at the University of Paris VII under the direction of Lê Dũng Tráng. She then completed her habilitation at the University of Bonn in 1985. Afterwards, she was a Heisenberg scholar at the MPI in Bonn and maître de conférence in Paris VII. In 1990, she became a full professor at the Universität Duisburg-Essen. In 2012, she moved to Berlin as the first Einstein Professor at the Freie Universität Berlin, where she became emerita in 2019. She continued her mathematical work and accepted a visiting professor position in 2019 at IAS Princeton. From there, she moved back to Europe in 2020. In the fall 2022, she held the Eilenberg Chair at Columbia University and is currently a part-time professor at Copenhagen University and a Faculty Associate at Harvard University. As a mathematician, she published more than 135 research articles with 45 coauthors covering a wide range of topics. In the following, only a small extract of her influential oeuvre is mentioned. In the 1980’s, she found together with Eckart Viehweg a new method to prove vanishing theorems in algebraic geometry. At the end of the 1990s, she gave with Vasudevan Srinivas and Viehweg the first general construction of an Albanese variety for singular projective varieties over an algebraically closed field. At the beginning of the 2000s, she proved that a Fano variety over a finite field has a rational point, answering positively a conjecture of Lang-Manin. She furthermore showed that a smooth projective variety over a local field with a regular model has a rational point in the special fiber if the étale cohomology of the generic fiber has coniveau 1. With Spencer Bloch and Pierre Berthelot, she proved that Serre’s Witt vector cohomology of a singular proper variety in positive characteristic is the slope <1 part of rigid cohomology, generalizing results of Bloch and Illusie in the smooth case. A spectacular result is her proof with Vikram Mehta in 2010 of a conjecture by Gieseker, which says, there are no non-constant stratified bundles on a geometrically simply connected smooth projective variety over a perfect field of positive characteristic. She proved with Bloch and Moritz Kerz a p-adic infinitesimal version of the Fontaine-Mazur conjecture. A result that recently has drawn much attention is her joint work with Michael Groechenig on the integrality of certain rigid local systems, which was conjectured by Carlos Simpson.Hélène Esnault has mentored about 25 PhD students and even more  postdocs. In recognition of her seminal contributions, she was awarded the Doisteau-Blutet prize of the Academy of Sciences in Paris in 2001, jointly with Eckart Viehweg  the Leibniz Prize in 2003 and received the Cantor medal of the German Mathematical Society in 2019. She received multiple honorary doctorates and was a member of various significant committees, including the Fields Medal Committee of the ICM 2018, the Structure Committee ICM 2022, the Shaw Prize Committee 2021-2020 and 2021-2025, and the Infosys Prize Committee 2023. Additionally, she has served on the editorial boards of several prestigious journals, including the Duke Mathematical Journal (since 1995), Mathematische Annalen (1998–2010), Mathematical Research Letters (since 2007), Algebra and Number Theory (since 2007 as a founding editor), Memoirs of the European Mathematical Society (since 2023), and Acta Mathematica (since 2023). The conference receives partial support from the GRK 2240: Algebro-geometric Methods in Algebra, Arithmetic and Topology

Michel Gros a officiellement pris sa retraite le 1er janvier de cette année. À cette occasion, ses collègues et amis souhaitent lui rendre hommage et célébrer une carrière remarquable, principalement axée sur la géométrie arithmétique, domaine dans lequel il a obtenu des contributions importantes sur des questions variées allant des cohomologies p-adiques et modulo p à la théorie des représentations, en passant par les régulateurs syntoniques. Michel a obtenu un doctorat en 1983 à Orsay, à l’issue d’une thèse intitulée « Classes de Chern et classes de cycles en cohomologie de Hodge-Witt logarithmique » dirigée par Luc Illusie. Après un séjour postdoctoral à l’Université de Tokyo auprès de Kazuya Kato, il a été recruté par le CNRS et affecté depuis les années 90 à l’Institut de Recherche Mathématique de Rennes où il participe à la vie scientifique du groupe initialement créé par Pierre Berthelot.Orateurs invités :- Cédric Pépin, Univ. Sorbonne Paris-Nord- Emanuel Reinecke, IHES- Simon Riche, Univ. Clermont Auvergne- Takeshi Tsuji, The University of TokyoOrganisateurs : Ahmed Abbes (CNRS & IHES), Fabrice Orgogozo (CNRS & IMJ-PRG) et Julien Sebag (Univ. de Rennes).

December 2023 marks Yvonne Choquet-Bruhat’s 100th birthday. For this special occasion, IHES organizes a day in her honor on December 8, 2023.Registration is free but mandatory.Yvonne Choquet-Bruhat’s work has had a long-lasting impact on the field of mathematical relativity starting with her seminal 1952 paper on the local well-posedness of Einstein equations. Her numerous contributions, both to constraint equations and to the evolution problem in general relativity, have deeply influenced several generations of researchers. This special day in her honor will be the occasion to present some of the latest developments in the field.Invited Speakers:Thibault Damour, IHES  Michael Eichmair, University of Vienna  Cécile Huneau, École polytechniqueSergiu Klainerman, Princeton University   Organizers: Laure Saint-Raymond (IHES) & Jérémie Szeftel (Laboratoire Jacques-Louis Lions)

En l’honneur du mathématicien Jacques Tits, un colloque de quatre demi-journées sur trois jours est organisé au Collège de France du 11 au 13 décembre 2023, organisé par Jean-Pierre Bourguignon, Michel Broué, Philippe Gille et Guy Rousseau. L’inscription au colloque est gratuite.Conférenciers invités :Michael BATEEmmanuel BREUILLARDPierre-Emmanuel CAPRACEJessica FINTZENAnne LONJOUTom DE MEDTSBernhard MÜHLHERRAnne QUÉGUINER-MATHIEUAnne PARREAUZev ROSENGARTENJean-Pierre SERREGernot STROTH Conseil scientifique :Michel BRIONNGÔ Bão ChâuAlain VALETTERichard WEISS

Combinatorics and Arithmetic for Physics: special daysTenth Anniversary EditionThe meeting focuses on questions of discrete mathematics and number theory, emphasizing computability. Problems are drawn mainly from theoretical physics: renormalization, combinatorial physics, geometry, evolution equations (commutative and noncommutative), or related to its models, but not only. Computations, based on combinatorial structures (graphs, trees, words, automata, semirings, bases), or classical structures (operators, Hopf algebras, evolution equations, special functions, categories) are good candidates for computer-based implementation and experimentation.Organized by: Gérard H. E. DUCHAMP, Maxim KONTSEVICH, Gleb KOSHEVOY, Sergei NECHAEV, and Karol A. PENSON.Speakers:Marek Bozejko (Institute of Mathematics Wroclaw University)Ricardo Buring (INRIA)Philippe Di Francesco (UIUC)Gérard H. E. Duchamp (LIPN, Université Paris Nord) Harold Erbin (CTP, MIT, USA)Stéphane Gaubert (INRIA, CMAP, École polytechnique)Volker Genz (IBS CGP)Darij Grinberg (Drexel University) Dimitry Gurevich (IITP, Moscou) Yuki Kanabuko (MPIM, Bonn)Rinat Kedem (UIUC)Maxim Kontsevich (IHES)Gleb Koshevoy (IITP, Moscow & IHES)Thomas Krajewski (CPT, Marseille)Marek Kus (Center for Theoretical Physics)Hiroaki Nakamura (Osaka University) Toshiki Nakashima (Sophia University Tokyo) Hadrien Notarantonio (Inria Saclay)Karol A. Penson (LPTMC, Sorbonne Université) Eric Pichon-Pharabod (Université Paris-Saclay)Sanjaye Ramgoolam (Queen Mary University of London)Travis Scrimshaw (Hokkaido University) Andrea Sportiello (LIPN, Université Paris Nord)Adrian Tanasa (Université de Bordeaux)Vasily Sazonov (CEA)Jean-Bernard Zuber (LPTHE, Sorbonne Université)Karol Życzkowski (Jagiellonian University)Sponsors: IHES – Math-STIC – LIPN (UMR-7030) – LPTMC (Univ-Paris 6) – INRIA – GDR EFI – CEAScientific Committee:Joseph Ben Geloun (LIPN-Paris XIII), Alin Bostan (INRIA), Marek Bozejko (Wroclaw University), Vincent Rivasseau (Orsay-CEA)

French Japanese Conference on Probability & Interactions6-8 March 2024at IHES – Marilyn and James Simons Conference CenterHow to get to IHESThe conference aims at gathering French and Japanese researchers sharing common interests in probability theory related to physical phenomena. Various themes will be considered such as random matrices, stochastic PDEs, particle systems, models in disordered media. Although these domains are represented by different communities, the conference will be the occasion to analyze the connections that occur between those different thematics and to strengthen the collaborations between researchers of both countries.Speakers:Ismael Bailleul, Université de Bretagne OccidentaleQuentin Berger, Sorbonne UniversitéMireille Capitaine, Institut de Mathématiques de ToulouseNicolas Curien, Université Paris-SaclayNizar Demni, Aix-Marseille UniversitéClément Erignoux, Inria Lille Nord-Europe et Université de Lyon 1Masato Hoshino, Osaka UniversityTakashi Imamura (Chiba University)Naotaka Kajino, Kyoto UniversityMylène Maïda, Université de LilleKirone Mallick, CEA, IPhTShuta Nakajima, Meiji UniversityIzumi Okada, Chiba UniversityAkira Sakai, Hokkaido UniversityTomoyuki Shirai, Kyushu UniversityRyokichi Tanaka, Kyoto UniversityMilica Tomasevic, CNRS, École polytechniqueCristina Toninelli, CNRS, Université Paris Dauphine – PSLKenkichi Tsunoda, Kyushu UniversityJulien Vovelle, CNRS, ENS LyonScientific committee:Charles Bordenave (CNRS, Aix-Marseille Université), Benoît Collins (Kyoto University), Arnaud Debussche (ENS Rennes), Takashi Kumagai (Waseda University), Grégory Miermont (ENS Lyon), Tomohiro Sasamoto (Tokyo Institute of Technology).Organizing committee: Anne de Bouard (CNRS, École polytechnique), Thierry Bodineau (CNRS, IHES), Reika Fukuizumi (Waseda University).

Arithmetic Algebraic GeometryJan Nekovář was a mathematician who worked and has made many significant and seminal contributions to algebraic geometry. He left us prematurely in November 2022. Here is a tribute note (in French) by Pierre Colmez.In his memory, Anna Cadoret, IMJ-PRG, Wiesława Nizioł, IMJ-PRG, and Sarah Zerbes, ETH Zürich, organize a conference in arithmetic algebraic geometry at IHES from October 9th to 13th, 2023.This is an international conference in arithmetic geometry, aimed at covering some of the most recent advances in the field with a focus on the areas Jan Nekovář was interested in. Invited Speakers:Tomoyuki Abe, IPMU – University of Tokyo  Spencer Bloch, University of Chicago  Ana Caraiani, Imperial College London – University of BonnHenri  Darmon, McGill University  Vesselin Dimitrov, Institute for Advanced Studies  Matthew  Emerton, University of Chicago  Veronika  Ertl, Universitat Regensburg  Hélène Esnault, Frei Universität Berlin  Olivier Fouquet, Université de Franche-Comté Alexander Goncharov, Yale University  Giada Grossi, CNRS, Université Sorbonne Paris Nord      Jie Lin, Universität Duisburg-Essen  David  Loeffler, University of Warwick   Akhil Mathew, University of Chicago   James Newton, University of Oxford  Alexander Petrov, Harvard University  Alena Pirutka, New York University  Tony Scholl, University of Cambridge   Yunqing Tang, University of California – Berkeley  Jacob Tsimerman, University of Toronto    IHES thanks all the donors of the 2021 Friends of IHES Gala for making this conference possible.

À l’occasion du centenaire de la naissance de René Thom, l’IHES organise trois jours de conférence les 20, 21 et 22 septembre 2023. Conférenciers invités : Norbert A’Campo, Univ. De BâleDaniel Bennequin, Institut Mathématique de Jussieu (IMJ-PRG)Alain Chenciner, IMCCE/Observatoire de Paris Antoine Danchin, Institut Pasteur                     Ivar Ekeland, Université Paris-DauphineSara Franceschelli, ENS LyonEmmanuel Giroux, CNRS et ENSMikhail Gromov, IHESKrzysztof Kurdyka, Université Savoie Mont BlancCherif Matta, Mount Saint Vincent University, Halifax, CanadaJean Petitot, EHESSOscar Randal-Williams, Université de CambridgeAna Rechtman, Université Grenoble-AlpesDennis Sullivan, City University of New York, Graduate Center                       Bernard Teissier, IMJ-PRGWolfgang Wildgen, Université de BrêmeComité scientifique : Marie-Claude Arnaud, IMJ-PRG, Marc Chaperon, IMJ-PRG, coordinateur, Antoine Danchin, Institut Pasteur, Yakov Eliashberg, Stanford University, Maxim Kontsevich, IHES, Cédric Villani, Université Lyon I & IHESComité d’organisation : Jean-Pierre Bourguignon, IHESRené Thom (1923-2002)Professeur permanent à l’IHES de 1963 à 1990René Thom a couvert un champ scientifique immense : d’abord en ouvrant des champs nouveaux en topologie, cette branche des mathématiques qui s’intéresse aux formes à déformation près, et dans l’étude de la dynamique. Il a ensuite créé une « mathématique de la morphogenèse », proposant des modèles pour la biologie et aussi pour les sciences humaines.Ces proposi­tions, souvent regroupées sous le nom de « théorie des catastrophes », ont quelque fois été controversées. René Thom a consacré la suite de sa vie scientifique à l’étude de la biologie théorique et surtout à la philosophie aristotélicienne.

“Wall-Crossing Structures, Analyticity, and Resurgence”,  a mini-school organized by Maxim Kontsevich and Yan Soibelman This conference is organized by Maxim Kontsevich (IHES), and Yan Soibelman (Kansas State University).The main emphasis will be on the new approach to resurgent series via analytic wall-crossing structures (an alternative to the traditional alien calculus), as well as the detailed study of examples coming from quantum Chern-Simons theory, WKB expansions and, more generally, holomorphic Floer theory.The program includes 3 mini-courses, given by:Jørgen E. Andersen (SDU)Maxim Kontsevich (IHES)Yan Soibelman (Kansas State University)and research presentations, given by:Philip Boalch (IMJ-PRG)Pierrick Bousseau (University of Georgia)Veronica Fantini (IHES)Segei Gukov (Caltech)Lotte Hollands (Heriot Watt University)Kohei Iwaki (The University of Tokyo)Marcos Mariño (University of Geneva)William Mistegård (SDU)David Sauzin (Observatoire de Paris-Meudon)Campbell Wheeler (MPI Bonn)

A Multiscale tour of Harmonic Analysis and Machine LearningTo Celebrate Stéphane Mallat’s 60th birthdayStéphane Mallat, professor at the Collège de France in data science, will be honored during a three-day workshop, April 19-21, 2023, organized by Joan Bruna, New York Univ., and Gabriel Peyré, CNRS-ENS, on the occasion of his 60th birthday. The purpose of this meeting is to bring together some of the characters of Data Analysis and Machine Learning, past, present, and future – and to celebrate the 60th birthday of a leading one, Stéphane Mallat, professor at Collège de France.His journey through Harmonic Analysis, Machine Learning, and Physics has profoundly influenced how these areas have evolved and blended together, and are now breaking new ground in our theoretical understanding of modern data analysis.Speakers:Akram Aldroubi, VanderbiltFrancis Bach, INRIARichard Baraniuk, RiceFreddy Bruckstein, TechnionEmmanuel Candès, StanfordMaureen Clerc, INRIAMaarten De Hoop, RiceDave Donoho, StanfordMichael Elad, TechnionRémi Gribonval, INRIAStéphane Jaffard, CréteilJérôme Kalifa, Let it CareHamid Krim, North Carolina State UniversityGitta Kutyniok, MünchenYann LeCun, New York University, and MetaEric Moulines, PolytechniqueEdouard Oyallon, CNRS and SorbonneNaoki Saito, UC DavisGuillermo Sapiro, DukeShihab Shamma, MarylandEero Simoncelli, New York UniversityJean-Jacques Slotine, MITMichael Unser, EPFLMartin Vetterli, EPFLIrène Waldspurger, CNRS and DauphineBin Yu, Berkeley 

Advances in Nonlinear Analysis and Nonlinear WavesFrank Merle, a mathematician, and holder of the Université de Cergy-Pontoise – IHES Chair in Analysis has made many important and seminal contributions to the qualitative study of solutions of nonlinear partial differential equations coming from Physics. Merle’s work has been pioneering in the sharp analysis of blowup solutions, and the collision of solitons, as well as in the soliton resolution conjecture. His groundbreaking works have been very influential in the field and beyond.Throughout his career, Frank Merle received many distinctions, including:ICM Invited Speaker (1998)Bôcher Memorial Prize – American Mathematical Society (2005)Silver Medal – Centre National de la Recherche Scientifique (2005)ERC Advanced Grant « Blow-up, Dispersion and Solitons » (2011)ICM Plenary Speaker (2014)Grand prix Ampère de l’électricité de France – French Academy of Sciences (2018)Member of the Academia Europaea (2020)The scientific objective of the conference is twofold. First, several experts in the field of dispersive and wave equations will present their recent advances. A second objective is to propose some conferences in analysis beyond the field of dispersive PDEs. The Scientific Committee hopes that all talks will be accessible to a general audience in analysis.Scientific Committee: M. Dafermos, A.-L. Dalibard, H. Duminil-Copin, T. Duyckaerts, E. Hebey, Y. Martel, G. Ponce, P. Raphaël, L. Saint-Raymond et H. ZaagOrganising Committee: C. Collot, R. Côte, F. Demengel, T. Duyckaerts, J. Jendrej, Y. Lan, E. Logak, Y. Martel, C. Muñoz, P. Raphaël, J. Szeftel, N. Tzvetkov et H. ZaagInvited Speakers:Henri Berestycki, EHESSNicolas Burq, Université de Paris-SaclaySimon Brendle, Columbia UniversityMaria Colombo, EPFLCamillo De Lellis, IASThierry Giamarchi, Université de GenèveFrançois Golse, École polytechniqueOana Ivanovici, CNRS & Sorbonne UniversitéCarlos Kenig, University of ChicagoSergiu Klainerman, Princeton UniversityPierre-Louis Lions, Collège de FranceNader Masmoudi, NYUHiroshi Matano, Meiji UniversityAndrea Nahmod, University of MassachusettsFelix Otto, Max-Planck Institut fur MathematikPierre Raphaël, University of CambridgeIgor Rodnianski, Princeton UniversityWilhelm Schlag, Yale UniversitySylvia Serfaty, NYUDaniel Tataru, UC BerkeleyLuis Vega, BCAMSijue Wu, University of MichiganThis event will be held at IHES, Bures-sur-Yvette, and at CY Advanced Studies, and is open to all.Registration is free and open until April 21, 2022.