Workshop

Workshop on Discrete & Continuous Aspects of Reaction-Diffusion in Pattern Formation (DiCoRD2026)

July 22 (Wed) - 24 (Fri) 2026

Ryoko Oishi-Tomiyasu (Professor, Institute of Mathematics for Industry, Kyushu University)
Makoto Sato (Professor, Kanazawa University)
Nobuhiko Suematsu (Professor, School of Interdisciplinary Mathematical Sciences, Meiji University)
Yasumasa Nishiura (Professor Emeritus, Hokkaido University)
Riccardo Muolo (Special Postdoctoral Researcher, Division of Fundamental Mathematical Science, RIKEN Center for Interdisciplinary Theoretical and Mathematical Sciences (iTHEMS))
Jonathan Dawes (Professor, University of Bath, UK)
Henrik Weyer (Postdoctoral Scholar, University of California, Santa Barbara, USA)
Yuzuru Kato (Associate Professor, Department of Complex and Intelligent Systems, School of Systems Information Science, Future University-Hakodate)
Ayumi Ozawa (Young Research Fellow, Japan Agency for Marine-Earth Science and Technology (JAMSTEC))
Takanori Sugimoto (Associate Professor, Faculty of Engineering Science, Kansai University)
Natsuhiko Yoshinaga (Professor, School of Systems Information Science, Future University-Hakodate)
Jens Rademacher (Professor, University of Hamburg, Germany)
Takeshi Fukao (Professor, Faculty of Advanced Science and Technology, Ryukoku University)
Yoshitaro Tanaka (Associate Professor, School of Systems Information Science, Future University-Hakodate)
Shuji Ishihara (Project Associate Professor, The University of Tokyo)
Hiroshi Ishii (Assistant Professor, Research Institute for Electronic Science, Hokkaido University)
Takeshi Watanabe (Associate Professor, Nagano University)
Antoine Diez (Research Scientist, Mathematical Application Research Team, Division of Applied Mathematical Science, RIKEN Center for Interdisciplinary Theoretical and Mathematical Sciences (iTHEMS))

Venue: via Zoom / Research Seminar Room 3, 6F, High-Rise Building, Meiji University (Nakano Campus)

Event Official Language: English

Joint Seminar on Cosmology

July 13 (Mon) 13:30 - 18:00, 2026

Yukihiro Kanda (Project Researcher, Institute for Cosmic Ray Research (ICRR), The University of Tokyo)
Fumiya Okamatsu (Research Assistant, Department of Physics, College of Humanities and Sciences, Nihon University)
Fumiya Sano (JSPS Postdoctoral Research Fellow, Graduate School of Arts and Sciences, The University of Tokyo)

The Joint Seminar is a collaborative seminar series organized by universities and research institutes in and around Tokyo. It is held once every one or two months, with the venue rotating among the participating institutions. At each meeting, we have around three talks and open, informal discussions. After the seminar, participants are also welcome to join an informal social gathering.

Venue: Okochi Hall

Event Official Language: English

The First RIKEN Quantum International Workshop on Frontiers of Quantum Computing Applications and Quantum-HPC Integration

May 25 (Mon) - 26 (Tue) 2026

This two-day workshop will bring together leading experts from academia, industry, and national laboratories to explore the rapidly evolving frontiers of quantum computing applications and their integration with high-performance computing (HPC) platforms. Hosted by RIKEN Quantum, the event will provide a forum for discussing recent advances, practical challenges, and future directions toward achieving utility-scale quantum computations and robust quantum–HPC hybrid workflows. The workshop is primarily an in-person event, but a special session on quantum computing in chemistry and life sciences will also be accessible via Zoom.

Venue: 2F Large Conference Room, Administrative Headquarters, RIKEN Wako Campus

Event Official Language: English

Perspectives and applications of Koopman Operator Theory

March 19 (Thu) 9:00 - 18:00, 2026

Yoshihiko Susuki (Professor, Graduate School of Engineering, Kyoto University)
Hiroya Nakao (Professor, Department of Systems and Control Engineering, Institute of Science Tokyo)
Alexandre Mauroy (Associate Professor, Mathematics, University of Namur, Belgium)
Yuzuru Kato (Associate Professor, Department of Complex and Intelligent Systems, School of Systems Information Science, Future University-Hakodate)

PROGRAM: 9h45 - 10h15 Registration & Coffee 10h15 - 10h20 Opening Remarks - Satoshi Iso (RIKEN), Director of iTHEMS 10h20 - 11h20 SESSION 1 - Chair: Tetsuo Hatsuda (RIKEN) Yoshihiko Susuki (Kyoto University): Koopman resolvents in dynamical systems and control 11h20 -11h40 Free Discussions 11h40 - 13h00 Lunch Break & Discussions 13h00-14h00 SESSION 2 - Chair: Narumi Fujii (Institute of Science Tokyo) Alexandre Mauroy (University of Namur, Belgium): Analytic EDMD method for spectral analysis of fixed point dynamics 14h00 - 14h30 Coffee Break & Discussions 14h30 - 15h30 SESSION 3 - Chair: Tetsuo Hatsuda (RIKEN) Hiroya Nakao (Institute of Science Tokyo): Koopman operator analysis of coupled oscillator systems 15h30 - 16h00 Coffee Break & Discussions 16h00 - 17h00 SESSION 4 - Chair: Riccardo Muolo (RIKEN) Yuzuru Kato (Future University Hakodate): Analysis of quantum nonlinear oscillators on the basis of Koopman operator theory 17h00 - 17h05 Closing Remarks - Tetsuo Hatsuda, Chair of the Workshop 17h05 - 18h00 Free Discussions

Venue: Room 535-537, 5F, Main Research Building

Event Official Language: English

KEK-iTHEMS Workshop “Concepts of Quantum and Spacetime”

March 9 (Mon) - 12 (Thu) 2026

The two fundamental questions—“What is quantum?” and “What is spacetime?”—are deeply intertwined. On one hand, the formulation and interpretation of quantum theory depend both implicitly and explicitly on our conceptions of time and space. On the other hand, we believe that fully taking into account the quantum character of nature will force us to revise our understanding of spacetime. These two conceptual problems lie at the heart of the unsolved challenge of how to quantize classical spacetime, and conversely, how (semi-) classical descriptions of spacetime emerge from quantum theory. Furthermore, if the entire matter-spacetime system is a kind of quantum many-body system, thermodynamics—which governs its statistical behaviors—should play a key role in elucidating these problems. This workshop will discuss the question “How can quantum theory and spacetime be understood in a consistent manner?” from a fundamental and broad perspective. To tackle this challenge, we gather researchers in foundations of quantum theory, quantum gravity, and related fields from around the world, providing a "space and time" to share various ideas with open minds and engage in lively discussions. By exploring new concepts and principles, we hope to uncover directions to guide quantum theory over the next 100 years. This workshop covers… Foundations of quantum theory Quantum gravity and emergence of spacetime Formulation of semi-classical gravity Experimental aspects of fundamental properties in nature and quantum gravity Foundations of quantum many-body systems and thermodynamics Other related topics are welcome. We welcome short talk presentations and poster presentations. This event is a workshop jointly organized by KEK Theory Center and RIKEN iTHEMS.

Venue: Seminar Hall, Building 3, KEK

Event Official Language: English

RIKEN-Nara Women's University Joint Diversity Promotion Workshop 2026

March 2 (Mon) - 3 (Tue) 2026

The RIKEN Center for Interdisciplinary Theoretical and Mathematical Sciences (iTHEMS) and the Faculty of Science at Nara Women's University are promoting a project to foster female researchers under the auspices of the RIKEN Diversity Promotion Office. As part of the program, 21 undergraduate and graduate students from Nara Women's University will visit several laboratories on the RIKEN Wako campus to ask questions about their research and hold workshops with iTHEMS researchers. Organizers: RIKEN Center for Interdisciplinary Theoretical and Mathematical Sciences (iTHEMS) Faculty of Science, Nara Women's University March 2 (Mon) 13:15-14:15 Center for Brain Science (CBS) (C56 Ikenohata Building) Laboratory for Multi-scale Biological Psychiatry (Team Director: Akiko Hayashi-Takagi) 14:30-15:45 Center for Interdisciplinary Theoretical and Mathematical Sciences (iTHEMS) (C01 Main Research Building, 4th Floor Rooms 435-437) Introduction to iTHEMS: Tetsuo Hatsuda (iTHEMS Division Director of Applied Mathematical Science) Lecture and Q&A: Megumi Oya (iTHEMS Medical Science Data-driven Mathematics Team Postdoctoral Researcher) 16:00-17:30 Center for Interdisciplinary Theoretical and Mathematical Sciences (iTHEMS) (C01 Main Research Building, 4th Floor Rooms 435-437) Lecture and Q&A: Leo Spiedel (iTHEMS ECL Research Unit Leader) 18:00-20:30 Networking Session (C01, Research Main Building 3F East Side (Okochi Hall Side)) March 3 (Tue) 9:00-10:30 RIBF Facility, RIKEN Nishina Center (RNC) 11:15-12:00 Center for Quantum Computing (RQC) Optical Quantum Control Research Team (Team Director: Hidehiro Yonezawa)

Venue: RIKEN Wako Campus

Event Official Language: Japanese

RIKEN iTHEMS-Kyoto University joint workshop on Asymptotics in Astrophysics and Cosmology

March 2 (Mon) - 4 (Wed) 2026

This joint workshop will bring together physicists and mathematicians who work with asymptotics and perturbation theory techniques. This includes theorists in cosmology, high energy physics, quantum gravity, solar physics, astrophysics. Workshop overview Over three days, there will be approximately 15 invited (1 hour slot) or contributed (20-30 min slot) talks about: Fundamental asymptotics and perturbation theory techniques used in theoretical physics. Various applications of asymptotics and perturbation theory techniques in (wave transport or oscillation related) astrophysics and cosmology eigenvalue problems. The workshop will also feature hands-on Mathematica and Python tutorials introducing: Practical use of WKB methods in applied mathematics for any “Schrodinger-like” wave equations, Resummation methods in high energy theory, Deriving normal modes in stars, and their application to tidal evolution in binary star or planet systems, Eigenvalue problems in core collapse supernova theory.

Venue: 8F, Integrated Innovation Building (IIB)

Event Official Language: English

International Workshop on Quantum Geometry

February 3 (Tue) - 6 (Fri) 2026

In recent years, quantum geometry has attracted a renewed interest as an important concept in physics, and is being actively studied in a wide variety of fields ranging from condensed matter physics to high-energy physics. This international workshop aims to invite researchers actively working at the forefront of quantum geometry research and hold intensive discussions, thereby providing an opportunity to facilitate mutual interaction that will lead to future collaborations. The workshop will cover a wide range of topics related to quantum geometry, as in condensed matter physics, AMO physics, quantum gravity, quantum information, etc.

Venue: 1F, Lecture Room #112, Information Science Bldg. (C43) (Main Venue) / Satellite : 4F, "Common Space" of FQSP, Information Science Bldg.(C43)

Event Official Language: English

Mathematical Sciences Outreach Workshop 2025

November 14 (Fri) - 16 (Sun) 2025

This year's meeting on "Outreach of Mathematical Sciences" will be held from FRI NOV 14 12:30 to SUN NOV 16 15:00 as a face-to-face meeting at Institute of Mathematics for Industry of Kyushu University as "Outreach of Data Descriptive Science and Mathematical Sciences" supported by Grant-in-Aid for Transformative Research Areas (A), 2022-2026 "Establishing data descriptive science and its cross-disciplinary applications" in cooperation with RIKEN iTHEMS SUURI-COOL (Kyushu) using ZOOM for the necessary part as well.

Venue: W1-D-413, IMI Auditorium, Ito Campus, Kyushu University (Main Venue) / via Zoom

Event Official Language: Japanese

RIKEN–Berkeley Workshop on Quantum Gravity 2025

October 23 (Thu) - 24 (Fri) 2025

This workshop will serve as the first meeting of the collaboration between the Leinweber Institute for Theoretical Physics (LITP) at the University of California Berkeley and the RIKEN Center for Interdisciplinary Theoretical and Mathematical Sciences (iTHEMS). Participation is open and researchers from other institutions are welcome to attend. The workshop will feature talks on recent developments in the field of Quantum Gravity and other relevant topics.

Venue: via Zoom / #359 (23rd Morning) & #435-437 (23rd Afternoon & 24th Morning), Main Research Building

Event Official Language: English

Japan-UK Workshop on Quantum Gravity

September 22 (Mon) - 26 (Fri) 2025

The universe at extremely early times is expected to be described by some theory of quantum gravity, although we still do not know precisely what quantum gravity actually is. In modern approaches to quantum gravity, the path integral point of view provides a fundamental framework towards answering this pressing question. However, an evaluation or even just a precise definition of the path-integral for a full-fledged quantum gravity is one of the most important open problems in modern theoretical physics.

Venue: 8F, Integrated Innovation Building (IIB)

Event Official Language: English

Functional Renormalization Group at RIKEN 2025

August 25 (Mon) - 26 (Tue) 2025

Functional Renormalization Group (FRG) is a powerful theoretical framework for investigating physical systems described by field theory. Its applications span a wide range of areas, from condensed matter and statistical physics to particle physics and gravity. This two-day workshop aims to provide an overview of recent applications and developments of FRG across various fields, foster discussions on future directions, and explore opportunities for new collaborations.

Venue: #345-347, Main Research Building, RIKEN Wako Campus

Event Official Language: English

iTHEMS-NCTS Workshop

August 18 (Mon) - 21 (Thu) 2025

This workshop aims to strengthen collaboration between researchers at RIKEN iTHEMS and the National Center for Theoretical Sciences in Taiwan. It will be a four-day event, with the first two days dedicated to interdisciplinary topics. The last two days will focus on specialized areas, with one day devoted to condensed matter physics and the other to high-energy physics, including quantum gravity.

Venue: via Zoom / RIKEN Wako Campus

Event Official Language: English

Crossroads of Virology and Mathematical Sciences

August 8 (Fri) 9:30 - 17:30, 2025

Makoto Takeda (Professor, Graduate School of Medicine, The University of Tokyo)
Yasuyuki Yamaji (Professor, Graduate School of Agricultural and Life Sciences, The University of Tokyo)
Kotaro Kiga (Director, Japan Institute for Helth Security)
Daishi Fujita (Associate Professor, Kyoto University Institute for Advanced Study (KUIAS))
Miyuki Koiso (Professor Emeritus, Kyushu University)
Daisuke Kuroda (Associate Professor, Department of Biosciences, College of Humanities and Sciences, Nihon University)
Catherine Beauchemin (Deputy Director, RIKEN Center for Interdisciplinary Theoretical and Mathematical Sciences (iTHEMS))
Shinichi Tanigawa (Associate Professor, Graduate School of Information Science and Technology, The University of Tokyo)
Takao Hashiguchi (Professor, Institute for Life And Medical Sciences, Kyoto University)
Hideo Fukuhara (Associate Professor, International Institute for Zoonosis Control, Hokkaido University)
Shohei Kojima (Special Postdoctoral Researcher, Genome Immunobiology RIKEN Hakubi Research Team, RIKEN Center for Integrative Medical Sciences (IMS))
Shuhei Miyashita (Assistant Professor, Graduate School of Agricultural Science, Tohoku University)
Ryoko Oishi-Tomiyasu (Professor, Institute of Mathematics for Industry, Kyushu University)
Suzuki Yuta (Principal Investigator, Japan Science and Technology Agency (JST))
Adnan Sljoka (Research Scientist, Molecular Informatics Team, RIKEN Center for Advanced Intelligence Project (AIP))

By creating a shared space for dialogue, we aim to stimulate new research directions and foster collaborative insights through the integration of mathematical sciences into studies of both the structural principles that govern viral form and function, and the dynamics of viral replication. We invite participation from both mathematical and theoretical scientists interested in the structure and replication mechanisms of viruses, as well as virologists who are open to exploring the potential of mathematical abstraction. Program: Morning Session I (Viruses) 10:00–10:20 Measles virus engineering Makoto Takeda (The University of Tokyo, Graduate School of Medicine) 10:20–10:40 Plant immunity to potexviruses Yasuyuki Yamaji (The University of Tokyo, Graduate School of Agricultural and Life Sciences) 10:40–11:00 Sophisticated phage infection strategies and bacterial defense responses Kotaro Kiga (National Institute of Infectious Diseases) Break (11:00–11:15) Morning Session II (Molecules, Math) 11:15–11:35 Designing Polyhedral Molecular Architectures at Will Daishi Fujita (Kyoto University, Institute for Advanced Study) 11:35–11:55 Anisotropic energy and (curved) polyhedron Miyuki Koiso (Kyushu University) 11:55–12:15 Nature-Inspired Design of Two-Component Protein Assemblies: From Cytoskeleton-Like to Virus-Like Structures Yuta Suzuki (JST PRESTO) Lunch Break (12:15–13:20) Afternoon Session I (Comp Sci, Math) 13:20–13:40 Computer-aided antibody design Daisuke Kuroda (Nihon University, Department of Life Sciences) 13:40–14:00 Revealing Protein Allostery and Functional Dynamics via Rigidity Theory and NMR Adnan Sljoka（RIKEN AIP） 14:00–14:20 Using mathematical models to identify experimental pitfalls when probing virus replication in vitro Catherine Beauchemin (RIKEN iTHEMS) 14:20–14:40 Combinatorics behind statics and flexibility of graphs Shinichi Tanigawa (The University of Tokyo, Graduate School of Information Science and Technology) Break (14:40–14:55) Afternoon Session II (Structures) 14:55–15:15 Glycoprotein structures in human pathogenic RNA viruses Takao Hashiguchi (Kyoto University, Graduate School of Medicine and Biomedical Sciences) 15:15–15:35 Introduction of cryo-electron microscopy facilities at Hokkaido University Hideo Fukuhara (Hokkaido University, Research Center for Zoonosis Control) Break (15:35–15:50) Afternoon Session III (Viruses, Math) 15:50–16:10 Human genetics during virus infection Shohei Kojima (Keio University, Bio2Q) 16:10–16:30 Suicidal population resistance of land plants against viruses Shuhei Miyashita (Tohoku University, Graduate School of Agricultural Science) 16:30–16:50 Mathematical and crystallographic perspectives in virology Ryoko Tomiyasu (Kyushu University, IMI) Organizers: Catherine Beauchemin (RIKEN iTHEMS) Makoto Takeda (University of Tokyo, Graduate School of Medicine) Ryoko Tomiyasu (Kyushu University, IMI)

Venue: #359, 3F, Main Research Building (Main Venue) / via Zoom