Balzan Conference on Open Issues in Gravitation    March 24-26, 2026    at IHES – Marilyn and James Simons Conference Center    How to get to IHES

The Balzan Conference on Open Issues in Gravitation is part of the research project carried out at IHES with the 2021 Balzan Prize for Gravitation: Physical and Astrophysical Aspects, awarded to T. Damour.
Though gravity is the oldest investigated interaction both observationally and theoretically, it remains mysterious and challenging in many aspects.This three-day conference will bring together leading experts in a wide range of topics related to gravitation. Besides offering an overview of the status of the field, the talks will address open issues in gravitation that are currently the focus of intense research, such as: gravitational waves, tests of  General Relativity, numerical relativity, self-force, new approaches to Black Hole perturbations, extreme black holes, BMS, post-Minkowskian gravity, scattering amplitudes, high-energy scattering, effective field theory, etc.
The talks will be videotaped, thereby completing the collection of Balzan Lectures at IHES (available on carmin.tv)
 

 
Organizing Committee:
Thibault Damour (IHES), Alessandro Nagar (INFN, Torino), Julio Parra Martinez (IHES)
Chairmen:
Luc Blanchet (CNRS-Institut d’Astrophysique de Paris), Gabriele Gionti (Specola, Vatican), Mikhail Volkov (Université de Tours)
Invited speakers:

Simone Albanesi (Friedrich-Schiller University Jena)

Zvi Bern (UCLA)

Donato Bini (IAC, CNR, Rome)

Marie-Anne Bizouard (ARTEMIS, Nice)

Alessandra Buonanno (Max-Planck Institute, Potsdam)
Manuela Campanelli (Rochester Inst. Tech.) – REMOTE

Alba Grassi (Université de Genève & CERN)

Marc Henneaux (International Solvay Institutes & Collège de France)

Gustav U. Jakobsen (Humbolt U., Berlin & Max Planck Inst., Potsdam)

Carlos Lousto (Rochester Inst. Tech.)

Simon Maenaut (Niels Bohr Institute, Copenhagen)

Pierpaolo Mastrolia (University of Padova) 
Keefe Mitman (Cornell University)

Ugo Moschella (Insubria U., Como & INFN, Milano)

Alessandro Nagar (INFN, Torino)
Julio Parra-Martinez (IHES)

Harvey Reall (University of Cambridge)

Jorge Santos (University of Cambridge) – REMOTE
Chiara Toldo (Université Libre de Bruxelles)
Filippo Vernizzi (IPhT, Saclay)
Niels Warburton (University College, Dublin)

 

The aim of this workshop is to bring together mathematicians and computer scientists around some talks on recent results from statistics, machine learning, and more generally data science research. Various topics in machine learning, optimization, deep learning, optimal transport, fairness, statistics will be presented. This workshop is particularly intended for doctoral and post-doctoral researchers.
 
Registration is free and open until March 27, 2026.
Invited speakers:Richard Combes (CentraleSupéléc)Hugo Cui (CNRS, Paris-Saclay)Ekhine Irurozki (Télécom Paris)Anna Korba (ENSAE)Paul Mangold (École polytechnique)Tabea Rebafka (AgroParisTech)
Organizers: Avetik Karagulyan (CNRS) & Erwan Le Pennec (École polytechnique)

Symmetry and Topology in Particle Physics    March 9-12, 2026    at IHES – Marilyn and James Simons Conference Center    How to get to IHES

 
In the past decade, sweeping progress in our understanding of quantum field theory (QFT) has revealed new organizing principles whose impact is already being felt across high energy, condensed matter, and mathematical physics. These include the generalization of the conventional principle of symmetries to include those that act on extended objects and/or do not come with an inverse. The goal of this workshop is to bring these new theoretical developments to bear on the problems of particle physics. The workshop aims to establish a new bridge between the formal and phenomenological high-energy physics communities, which will drive progress in both directions. 
 

 
Organizers:
Lea Bottini (IHES), Julio Parra Martinez (IHES), Alessandro Podo (IHES), Giovanni Rizi (IHES)
Scientific Committee:
Nathaniel Craig (UCSB), Clement Delcamp (IHES), Henriette Elvang (Michigan), LianTao Wang (Chicago)
Invited speakers:

Daniel Brennan (University of Birmingham)

Yichul Choi (Institute for Advanced Study)

Clay Córdova (University of Chicago)

Lucia Córdova (University of Amsterdam)

Nathaniel Craig (UC Santa Barbara)

Raffaele Tito D’Agnolo (IPhT, CEA Saclay/ENS)

Isabel García García (University of Washington)

Ben Gripaios (Cambridge University)

Diego García-Sepúlveda (Harvard University)

Sungwoo Hong (KAIST)

Po-Shen Hsin (King’s College London)

Seth Koren (University of Notre Dame)

Ho-Tat Lam (Stanford University) REMOTE TALK
Vazha Loladze (Oxford University)
Mario Reig (CERN)

Ling-Xiao Xu (ICTP)

 

French-Japanese Conference on Arithmetic Geometry in Honor of Takeshi Saito and Takeshi Tsuji        May 31 – June 4, 2027 at IHES – Marilyn and James Simons Conference Center    How to get to IHES

This conference, which is part of a long-standing tradition of French-Japanese collaboration in arithmetic geometry, will honor two leading figures of this partnership: Professor Takeshi Saito, on the occasion of his retirement, and Professor Takeshi Tsuji, on the occasion of his 60th birthday.
The main topics of the conference will include:

p-adic Hodge theory, including the p-adic Simpson correspondence, geometric Sen theory, p-adic Galois representations and (φ,Γ)-modules, prismatic cohomology, and their applications;

Ramification theory, including singular support and characteristic cycles of l-adic étale sheaves (in equal and mixed characteristic), compatibility with proper higher direct images, Swan conductors, and epsilon-factors;

Geometric Langlands theory, l-adic, p-adic, and for modules with integrable connections, in characteristic p and in characteristic 0.

 
Invited speakers:

Abhinandan (Sorbonne Université)
Tomoyuki Abe (IPMU, University of Tokyo)
Piotr Achinger (IMPAN & KSE)
Alexander Beilinson (University of Chicago)
Bhargav Bhatt (IAS & Princeton University)*
Ofer Gabber (CNRS & IHES)
David Hansen (National University of Singapore)
Tongmu He (Princeton University)
Haoyu Hu (Nanjing University)
Kazuhiro Ito (Tohoku University)
Hiroki Kato (IHES)
Kazuya Kato (University of Chicago)
Tong Liu (Purdue University)
Kojiro Matsumoto (University of Tokyo)
Yoichi Mieda (University of Tokyo)
Matthew Morrow (CNRS & Université Paris-Saclay)
Wiesława Nizioł (CNRS & Sorbonne Université)
Emanuel Reinecke (University of Copenhagen)
Ryotaro Sakamoto (University of Tsukuba)
Takumi Watanabe (University of Tokyo)
Daxin Xu (Morningside Center of Mathematics)
Mingjia Zhang (Princeton University)*
Weizhe Zheng (Morningside Center of Mathematics)

 
Organizers: 

Ahmed Abbes (CNRS, IHES)
Laurent Berger (ENS de Lyon)
Takashi Hara (Tsuda University)
Atsushi Shiho (University of Tokyo)
Yuri Yatagawa (Institute of Science Tokyo)

Organizing Committee: Daniel Baumann (Amsterdam and National Taiwan Univ.), Daniel Green (UC San Diego), Austin Joyce (Univ. of Chicago), Guilherme Pimentel (SNS Pisa).
Scientific Committee: Eiichiro Komatsu ((Max Planck Inst. for Astrophysics), Marilena LoVerde (Univ. of Washington), Eva Silverstein (Stanford Univ), Raman Sundrum (Univ. of Maryland).
The Summer School will be held at the Institut des Hautes Études Scientifiques (IHES) from July 6 to 17, 2026. IHES is located in Bures-sur-Yvette, south of Paris (40 minutes by train from Paris) – Access map
This school is open to everybody but intended primarily for young participants, including Ph.D. students and postdoctoral fellows. 
Deadline for applications: March 10, 2026

2026 IHES Summer School – Cosmological Correlators
The goal of this IHES school is to prepare students to make contributions to the study of cosmological correlations, both in the early and late universe. Theoretical cosmology as a discipline is increasingly crossing traditional subfield boundaries within high-energy physics. As a result, the full spectrum of topics and expertise students require cannot be simply contained in a single course.
This school aims to fill this gap by providing a holistic viewpoint on the diverse set of topics that students need to know, with an eye towards their applications in cosmology. There has been a remarkable amount of progress in the study of cosmological quantum field theory in the last few years, and a dedicated school focused on the diverse set of skills needed to contribute is much needed.
The school will have a set of courses given by world leaders in the subject, with the first week focused on EFT and bootstrap methods to compute cosmological correlators, and the second week devoted to more advanced topics and connections at the interface of particle theory and cosmology.
Speakers:

Dionysios Anninos (King’s College)
Scott Dodelson (Carnegie Mellon & Chicago Univ.)
Scott Melville (Queen Mary Univ. of London)
Enrico Pajer (DAMTP, Cambridge Univ.)
Claudia de Rham (Imperial College)
Marko Simonovic (Florence Univ.)
Charlotte Sleight (Univ. of Naples)
Massimo Taronna (Univ. of Naples)
Raffaele Tito D’Agnolo (IPhT CEA & ENS Paris)
Andrew Tolley (Imperial College)
Matias Zaldarriaga (IAS) 

 

 

Partial Differential Equations, Analysis and Geometry    A Conference in Honor of Sergiu Klainerman’s 75th Birthday    January 12-16 2026    at IHES – Marilyn and James Simons Conference Center    How to get to IHES
Registration is free but compulsory and open until December 31, 2025. 

Sergiu Klainerman, Eugene Higgins Professor of Mathematics at Princeton University, has made seminal contributions to nonlinear partial differential equations, analysis, differential geometry, and mathematical general relativity. He pioneered the vector field method for nonlinear wave equations, developed multilinear techniques for low-regularity analysis, and established landmark results on the stability of Minkowski space and Kerr black holes. His work has reshaped PDE, analysis, geometry, and relativity, training and inspiring generations of mathematicians.
Throughout his career, Sergiu Klainerman has received many distinctions, including:

Sloan Fellowship (1983–1985)

MacArthur Fellowship (1991–1996)

Guggenheim Fellowship (1997–1998)

Bôcher Memorial Prize, American Mathematical Society (1999)

Fellow of the American Academy of Arts and Sciences (1996)

Foreign Member of the French Academy of Sciences (2002)

Member of the U.S. National Academy of Sciences (2005)

Israel Gelfand Chair, IHÉS (2017–2019)

 
The conference will celebrate Sergiu Klainerman’s 75th birthday by bringing together experts to present recent advances in analysis, PDE, geometry, and general relativity, with the aim of fostering interaction across fields and engaging early-career researchers in these exciting developments.
Speakers:

Scott Armstrong (Sorbonne Université)
Thibault Damour (IHES)
Camillo De Lellis (IAS)
Patrick Gérard (Univ. Paris-Saclay, LMO)
Elena Giorgi (Columbia University)
Alexandru Ionescu (Princeton University)
Philip Isett (Caltech)
Jonathan Luk (Stanford University)
Sung-Jin Oh (UC Berkeley)
Duong Phong (Columbia University)

Richard Schoen (UC Irvine)

Sylvia Serfaty (Sorbonne Université)

Jacques Smulevici (Sorbonne Université)

Gigliola Staffilani (MIT)

Daniel Tataru (UC Berkeley)

Vlad Vicol (NYU)

Hong Wang (IHES & NYU)

Qian Wang (University of Oxford)

Pin Yu (Tsinghua University) 

Scientific committee:     Frank Merle (IHES & CY Cergy Paris Université), Jérémie Szeftel (Sorbonne Université)
Organizing committee:     Elena Giorgi (Columbia University), Markus Keel (University of Minnesota), Jérémie Szeftel (Sorbonne Université)
 

Combinatorics and Arithmetic for PhysicsThe 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 and Karol A. PENSON.
Speakers:

Cyril Banderier (LIPN)
Marek Bożejko (Wroclaw University)
Philippe Di Francesco (IPhT Saclay)
Vladimir Dotsenko (Université de Strasbourg)
Vladimir Fock (IRMA Strasbourg)
Oleg Kaikov (LIST, Saclay)
Arthemy Kiselev (University of Groningen)
Maxim Kontsevich (IHES)
Pierre-Vincent Koseleff (IMJ-PRG)
Gleb Koshevoy (IITP, Moscow)
Anastasia Matveeva (École polytechnique)
Thomas Müller (LIPN, Paris)
Hiroaki Nakamura (Osaka University)
Toshiki Nakashima (Sophia University Tokyo)
Lucas Pannier (Université de Versailles Saint-Quentin en Yvelines)
Karol Penson (LPTMC, Sorbonne Université)
Parham Radpay (Université Paris-Saclay)
Kilian Raschel (Université d’Angers)
Vladimir Roubtsov (Université d’Angers)
Thomas Simon (Université de Lille)
Reiko Toriumi (Okinawa Institute of Science and Technology)
 

Sponsors: IHES – Math-STIC – LIPN (UMR-7030) – LPTMC (Univ-Paris 6) –   INRIA – GDR EFI 
Scientific Committee:Joseph Ben Geloun (LIPN-Paris XIII), Alin Bostan (INRIA), Marek Bożejko (Wroclaw University), Vincent Rivasseau (Orsay-CEA), Pierre Simonnet (Univ. Corse)

 
 

13e séminaire ITZYKSON : Bootstrap conforme et géométrie spectrale

Le 13e séminaire Itzykson est organisé par Sylvain Ribault (IPhT Saclay), Slava Rychkov (IHES) et Pierre Vanhove (IPhT Saclay). 
Depuis une dizaine d’années l’axe math-physique de la FMJH organise un séminaire Itzykson tous les ans à l’IHES. Il s’agit d’une journée consacrée à un thème de physique mathématique, avec un cours et deux ou trois exposés spécialisés (en français ou en anglais selon le choix des orateurs).
Le prochain séminaire Itzykson portera sur la théorie conforme des champs, et ses liens avec la géométrie spectrale, et la théorie des nombres. Ces sujets sont reliés par la possibilité d’appliquer une même méthode: le bootstrap conforme. Le séminaire donnera des perspectives mathématiques et physiques sur des résultats récents, notamment au sujet des spectres des variétés hyperboliques, des fonctions L en théorie des nombres, et des spectres des théories conformes.
Un cours et deux exposés auront lieu dans la journée, présentés par : 

Dalimil Mazáč, IPhT Saclay & IHES

Frédéric Naud, Sorbonne Université, IMJ-PRG
Balt van Rees, CPHT, École polytechnique

L’inscription est gratuite mais nécessaire et sera possible jusqu’au 8 octobre 2025. Un buffet-déjeuner sera offert aux participants qui s’y seront inscrits. Le séminaire sera filmé et diffusé en différé sur la chaîne YouTube de l’IHES.

This one-day workshop is organised jointly by Huawei and IHES, as a part of the IHES-Huawei partnership. The aim of the workshop is to bring together prominent voices from academia and industry to explore the evolving role of causal reasoning in artificial intelligence. The workshop will deliver meaningful dialogue around two major directions. The first one is theory-driven causal modelling, which focuses on theoretical approaches, frameworks, and tools for understanding causality, emphasizing the development of rigorous methods to identify, estimate, and interpret causal relationships. The second topic is machine learning with causal AI and its applications, which integrates machine learning and deep learning techniques to improve causal discovery, causal inference, causal representation learning and their corresponding application fields.
INVITED SPEAKERS: 

BOWDEN Jack (Exeter University, UK)
CADEI Riccardo (EPFL, Switzerland)
FUNG Pascale (HKUST & Visiting Professor at the Central Acad. of Fine Arts in Beijing)
HENCKEL Leonard (Univ. College, Dublin, UK)
LI Haoxuan (Peking University)
LIMNIOS Myrto (EPFL, Switzerland)
TIAN Jin (MBZUAI, Abu Dhabi)
ZHOU Hong (Huawei)

 
 

 
 
Organisers: Keshuang Li (Huawei), Keli ZHANG (Huawei)

The goal of this conference is to advance the dialogue and interactions between the LLM community and the larger world of mathematics in order to further the mathematical understanding of LLMs and contribute to solving some of the outstanding problems in the new field of LLMs.
 
In particular we intend to investigate mathematical structures that can be used to understand LLMs in terms of what they implicitly learn and how. 
 
At the same time, in the opposite direction the use of LLMs in order to do mathematics will be investigated.
 
Registration is free and open until May 15, 2025.
Invited speakers:Katie Collins (Cambridge University)Yann Fleureau (Numina)Fabian Glöckle (Ecole Nationale des Ponts et Chaussées & FAIR at Meta, Paris)Javier Gómez-Serrano (Brown University)Timothy Gowers (Collège de France)Yann Ollivier (FAIR at Meta, Paris)Simon Frieder (Oxford University)
Organizers: François Charton (Meta AI Research), Michael Douglas (Harvard University & IHES), Amaury Hayat (CERMICS) & Yiannis Vlassopoulos (Athena Research Center & IHES)
 

New Structures and Techniques in p-adic Geometry        October 27-31, 2025 at IHES – Marilyn and James Simons Conference Center    How to get to IHES

In recent years, p-adic geometry has benefited from several new ideas. The goal of this conference is to invite experts to give lectures explaining some of these ideas and their uses.  The main themes are: motivic methods, categorical p-adic Langlands, and Igusa stacks.  Besides these mini-courses, there will also be some individual lectures by selected participants.
 Registration deadline: June 30, 2025
Speakers:

Johannes Anschütz (Université Paris-Saclay)
Ana Caraiani (Imperial College London)
Gabriel Dospinescu (CNRS, Université de Clermont-Auvergne)
Veronika Ertl (Université de Caen)
Eugen Hellmann (Universität Münster)
Kalyani Kansal (Imperial College London)
Dongryul Kim (Stanford University)
Arthur-César Le Bras (Université de Strasbourg)
Shubhodip Mondal (Purdue University)
Timo Richarz (TU Darmstadt)
Alberto Vezzani (Università degli Studi di Milano)
Mingjia Zhang (IAS, Princeton)

Organizing committee:     Dustin Clausen (IHES), Toby Gee (Imperial College London), Wiesława Nizioł (IMJ-PRG)
This conference is supported by the Simons Collaboration on Perfection in algebra, geometry, and topology

The aim of this workshop is to bring together mathematicians and computer scientists around some talks on recent results from statistics, machine learning, and more generally data science research. Various topics in machine learning, optimization, deep learning, optimal transport, fairness, statistics will be presented. This workshop is particularly intended for doctoral and post-doctoral researchers.
 
Registration is free and open until March 25, 2025.
Invited speakers:Anne Auger (Inria Saclay)Etienne Boursier (Inria, Université Paris-Saclay)Solenne Gaucher (École polytechnique)Charlotte Laclau (Télécom Paris)Arshak Minasyan (CentraleSupélec)Nicolas Vayatis (ENS Paris-Saclay)
Organizers: Evgenii Chzhen (Laboratoire de Mathématiques d’Orsay, Université Paris-Saclay)Erwan Le Pennec (École polytechnique)