Workshop

Foundations of Quantum Programming Mini-Workshop & Contributed Talks

September 28 (Mon) - October 2 (Fri) 2026

Mingsheng Ying (Professor, University of Technology Sydney, Australia)
Hiroyuki Ochiai (Professor, Institute of Mathematics for Industry, Kyushu University)
Jianjun Zhao (Professor, Kyushu University)
Minh Canh Do (Instructor, Japan Advanced Institute of Science and Technology)

Venue: Room C502, West Zone 1 Building D, Ito Campus, Kyushu University, SUURI-COOL (Kyushu) (Main Venue) / via Zoom

Event Official Language: English

Workshop on Gestalt

September 24 (Thu) - 30 (Wed) 2026

Ko Aoki (Postdoc, University of Copenhagen, Denmark)

Note. The lectures will be given in Japanese. This workshop will be jointly organized by RIKEN AIP. During this five-day workshop, we will hold a learning seminar and intensive lectures on gestalt theory, which was recently developed by Scholze and Stefanich. Gestalt theory is a new geometric framework that unifies various derived analytic geometry and higher sheaf theory, building on the foundations of higher and derived category theory. At this event, we will host Ko Aoki, who has contributed to the foundations and development of the theory, for the intensive lecture session. During the first three days of the workshop, we will feature tutorial lecture sessions, presented by the participants. All lectures will be given in Japanese, with the aim of promoting the dissemination and development of gestalt theory in Japan.

Venue: Yagami Campus, Keio University

Event Official Language: Japanese

Quantum Information: Entanglement of Mathematics & Physics

September 21 (Mon) - 23 (Wed) 2026

This workshop brings together mathematicians and physicists to explore the deep connections among quantum information, mathematics, and physics. Topics span quantum gravity, condensed matter physics, quantum computing, and quantum error correction, with an emphasis on the mathematical structures that underlie entanglement and quantum information across these fields. The program is designed to foster genuine cross-disciplinary dialogue, allowing ample time for discussion alongside formal talks. [Invited speakers] Akira Furusaki (RIKEN CEMS/iTHEMS) Marcel Franz (UBC / SBQMI) Ching-Kai Chiu (iTHEMS) Jasmin Bedow (UBC) Max McGinley (UBC) Yosuke Kubota (Kyoto University) Shunji Matsuura (RIKEN iTHEMS) Bartosz Regula (RIKEN RQC) Ryuji Takagi (University of Tokyo) Sisi Zhou (Perimeter Institute) Olivia Di Matteo (UBC / SBQMI) Daochen Wang (UBC Computer Science) Polina Feldmann (UBC) Masazumi Honda (RIKEN iTHEMS) Yasuyuki Kawahigashi (RIKEN iTHEMS) Carolyn Zhang (UBC) Masahito Yamazaki (Kavli IPMU, University of Tokyo) Aswin Parayil Mana (University of Tokyo) Alex May (Perimeter Institute) Masamichi Miyaji (RIKEN iTHEMS) Mark Van Raamsdonk (UBC Physics & Astronomy)

Venue: University of British Colombia / via Zoom

Event Official Language: English

1st MSS–COGNAC Joint Workshop

September 2 (Wed) 13:00 - 18:00, 2026

First joint workshop between Mathematical Social Science Team from iTHEMS and Computational Group Dynamics Collaboration Unit from CBS. We will introduce ourselves, discuss our research interests and ongoing projects, and explore potential collaborations between the two teams. Schedule 13:00–13:10 Welcome & brief introductions 13:10–13:30 Wataru Toyokawa (COGNAC) 13:30–13:50 Nikoleta Glynatsi (MSS) 13:50–14:10 Ryutaro Mori (COGNAC) 14:10–14:30 Yohsuke Murase (MSS) 14:30–14:50 Alex Witt (COGNAC) 14:50–15:00 Buffer / informal discussion 15:00–16:00 BTCC coffee break 16:00–16:20 Ivan Romic (MSS) 16:20–16:40 Katja Sangati (COGNAC / Kyoto University) 16:40–17:00 Brian Mintz (MSS) 17:00–17:20 Kazuya Horibe (COGNAC) 17:20–17:40 Shinobu Utsumi (MSS) 17:40–18:00 Natsuki Ogusu (COGNAC) 18:30– Banquet in Wako (venue TBA)

Venue: S305 Seminar Room, Brain Science Central Building, RIKEN Wako Campus

Event Official Language: English

UK-Japan Workshop on Quantum Gravity 2026

August 24 (Mon) - 28 (Fri) 2026

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. With the "UK-Japan Workshop on Quantum Gravity 2026" we want to bring together experts working on different aspects of the gravitational path-integral, such as Gravitational Scattering Amplitudes; Complex Geometries and Exact WKB; Quantum Cosmology; Exact Methods and Resurgence Analysis; with the long-term goal of providing innovative ways of tackling modern problems in quantum gravity. This workshop is the second event sponsored by the Royal Society International Collaboration Award Grant "Re-PaInt: A Resurgence Path-Integral approach to quantum gravity" shared between Masazumi Honda at Riken iTHEMS and Daniele Dorigoni at Durham University, and aimed at fostering and developing an international partnership between the two institutes, as well as the greater Japan and UK theoretical physics communities working on quantum gravity, broadly intended. The page for the 2025 meeting held at the RIKEN campus in Kobe can be found in the Related Links section below.

Venue: Durham University

Event Official Language: English

The 3rd NCTS-iTHEMS Joint Workshop on Theoretical, Mathematical, and Computational Sciences

August 18 (Tue) - 21 (Fri) 2026

The 3rd NCTS-iTHEMS Joint Workshop will be held from August 18 to 21, 2026, at National Taiwan University. Following the previous two editions, which focused mainly on theoretical physics, this year’s workshop marks a new stage in the partnership between RIKEN iTHEMS and NCTS. In particular, the workshop follows the signing of the iTHEMS-NCTS Collaboration Research Agreement in April 2026, which aims to further strengthen researcher exchange, international workshops, and joint research activities. With the participation of both the NCTS Physics and Mathematics Divisions, this year’s workshop broadens its scope from theoretical physics to the wider interface among theoretical, mathematical, and computational sciences. Key topics include high-energy physics and gravity, condensed matter physics, quantum computing and information, geometry and topology, applied mathematics, machine learning, and scientific AI. The program will feature plenary lectures, research talks, and a poster session, providing a platform for interdisciplinary exchange and future collaborations between iTHEMS and NCTS. Registration is open to the public. Feel free to sign up if you're interested! Venue NCTS Physics Lecture Hall, 4th Floor, Cosmology Hall, NTU Speakers Plenary Speakers Tan Bui-Thanh (UT Austin) Etera Livine (ENS Lyon) Tzu-Chieh Wei (SUNY Stony Brook) Invited Speakers Chi-Kang Chang (RIKEN iTHEMS) Chien-Yu Chou (RIKEN iTHEMS) Antoine Diez (RIKEN iTHEMS) Keita Goto (RIKEN iTHEMS) Ryusuke Hamazaki (RIKEN iTHEMS) Masazumi Honda (RIKEN iTHEMS / Saitama U) Muzi Hong (RIKEN iTHEMS) Masaaki Imaizumi (RIKEN AIP / U of Tokyo) Derek Inman (RIKEN iTHEMS) Isao Ishikawa (Kyoto U) Riccardo Muolo (RIKEN iTHEMS) Álvaro Pastor-Gutiérrez (RIKEN iTHEMS) Wei-Hsiang Shao (RIKEN iTHEMS) Chuan-Tsung Chan (Tunghai University) Po-Yao Chang (NTHU) Heng-Yu Chen (NTU) Hao-Chung Cheng (NTU) Hao-Wei Huang (NTHU) Yi-Ping Huang (NTHU) Jer-Lai Kuo (AS) Chia-Hsiang Lin (NCKU) Chin-Hung Lin (NYCU) Yu-Chen Shu (NCKU) Cheng-Fang Su (NYCU) Chiao-Hsuan Wang (NTU) (In alphabetical order of surnames) Organizing Committee Chi-Kang Chang (RIKEN iTHEMS) Che-Yu Chen (RIKEN iTHEMS) Ching-Kai Chiu (RIKEN iTHEMS) (co-chair) Pei-Ming Ho (NTU/NCTS) Masazumi Honda (RIKEN iTHEMS) Chang-Tse Hsieh (NTU/NCTS) (co-chair) Ming-Lun Hsieh (NTU/NCTS) Isao Ishikawa (Kyoto U) Satoshi Iso (RIKEN iTHEMS) Min-Hsiung Lin (NCKU/NCTS) Yuki Yokokura (RIKEN iTHEMS) (In alphabetical order of surnames)

Venue: NCTS Physics Lecture Hall, 4th Floor, Cosmology Hall, NTU

Event Official Language: English

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