Co-hosted by iTHEMS

The Theory of Periodic Tangles & Their Interdisciplinary Applications

July 28 (Mon) - August 1 (Fri) 2025

The mathematical characterization of entanglement holds immense potential for describing the mechanical functions of diverse physical systems and materials. A universal interdisciplinary study, involving scientists, engineers, and artists promises both advance of the field itself and significant contribution to the research and design of innovative solutions for textiles, medical devices, polymers, molecular chemistry, or construction materials among others. The program seeks an alternative to the trial–and–error approach, bringing together academia and industry to seek new sustainable solutions and inspiration, contributing to society. It will consist not only of scientific exchanges but will promote cultural impact by organizing exhibitions or hands–on workshops. Additionally, it will encourage several discussions by providing networking opportunities and utilizing the unique venue of House of Creativity at Tohoku University. This workshop will gather researchers from various disciplines and include invited lectures, a poster session, roundtable discussions, and brainstorming activities. Our focus will be on exploring the connections between knot theory and its applications in areas such as polymers and soft matter, textile mechanics, graphic design, and more. This event includes a joint symposium between the WPI–AIMR (Tohoku University) and WPI–SKCM2 (Hiroshima University) on Friday, August 1st, 2025: INTERWOVEN: A WPI–AIMR & WPI–SKCM2 Symposium, Towards a Universal Topological Model of Entangled Structures for Sustainable Metamaterials Please fill in the registration form by June 16th 2025. Confirmed speakers (alphabetical order): Jörn Dunkel (Massachusetts Institute of Technology) Yuanyuan Guo (Tohoku University) Tatsuki Hayama (Keio University) Louis H. Kauffman (University of Illinois at Chicago) Yuka Kotorii (Hiroshima University) Sofia Lambropoulou (National Technical University of Athens) Eleni Panagiotou (Arizona State University) Pedro M. Reis (École Polytechnique Fédérale de Lausanne) Takahiro Sakaue (Aoyama Gakuin University) Vanessa Sanchez (Rice University) Henry Segerman (Oklahoma State University) Koya Shimokawa (Ochanomizu University) Hiroshi Suito (Tohoku University) Ryuichi Tarumi (Osaka University) Hirofumi Wada (Ritsumeikan University) Please refer to the workshop website via the relevant link for more details. We are looking forward to your participation and to welcoming you to Sendai!

Venue: TOKYO ELECTRON House of Creativity, Katahira Campus, Tohoku University

Event Official Language: English

RIKEN Theory Symposium

July 9 (Wed) - 10 (Thu) 2025

This symposium will bring together leading theorists from the fields of artificial intelligence, quantum information, quantum field theory, quantum gravity, and related areas of mathematics. It aims to stimulate interactions and collaborations across these diverse fields by fostering cross-disciplinary dialogue. It is organized by RIKEN's Pioneering Research Institute (PRI) together with the Center for Interdisciplinary Theoretical and Mathematical Sciences (iTHEMS), and the Center for Advanced Intelligence Project (AIP). July, 9th (Wed.) 9:20- 9:30 Opening Remarks Dr. Hirosi Ooguri 9:30 - 10:15　Daniel Jafferis, “Tensor models for 3d gravity” 10:45 - 11:30 Sameer Murthy, “Supersymmetric index of black holes and black strings” Transportation by bus from Wako-campus is available for up to 60 people. Special AIP-PRI-iTHEMS joint seminar Venue: Tokyo Open Space (RIKEN Nihonbashi Campus) 14:30 - 15:15 Sergei Gukov, “Math + AI = AGI” 15:15 - 16:00 Masazumi Honda, “Fracton topological phases and Foliated field theories” 16:30 - 17:15 Richard Kueng, “Learning to predict ground state properties of gapped Hamiltonians” *Due to building access restrictions, this session is open only to participants of the morning session, RIKEN affiliates, or those who have completed the registration form. If you wish to attend, please register via the Related Links section below. July, 10th (Thur.) 9:30 - 10:15 Yifan Wang, “Pinning Defects, Fusion and Factorization” 10:45 - 11:30 Yichul Choi, “Non-Invertible Symmetry and Entanglement Entropy” 11:45 - 12:30 Yuya Kusuki, “Non-invertible Symmetries on Non-orientable Surfaces” 14:00 - 14:45 Heeyeon Kim, “3d TFTs from 4d N=2 BPS particles” 15:15 -16:00 Yuto Moriwaki, “On mathematical formulations of conformal field theory” 16:00 - 16:45 Kantaro Ohmori, “Higher Representation Theory and Excitations of Gauge Theories” 16:45 -16:55 Closing Remarks by Dr. Motoko Kotani Organizer: RIKEN Pioneering Research Institute (PRI) Co-organizers: RIKEN Center for Interdisciplinary Theoretical and Mathematical Sciences (iTHEMS) RIKEN Center for Advanced Intelligence Project (AIP)

Venue: Suzuki Umetaro Hall / Tokyo Open Space (COREDO Nihonbashi)

Event Official Language: English

From Quarks to Neutron Stars: Insights from kHz gravitational waves

April 23 (Wed) - 24 (Thu) 2025

Astronomical observations of binary neutron star mergers and supernovae provide unique opportunities to explore physics spanning from quarks to neutron stars. The groundbreaking multi-messenger observation of GW170817, combining electromagnetic signals and gravitational waves, vividly demonstrated this potential. Furthermore, if a core-collapse supernova were to occur in our galaxy, it would likely become the first event where electromagnetic signals, neutrinos, and gravitational waves are detected together. The interior of neutron stars is not yet well understood due to their extreme density, where exotic states of matter may emerge. Gravitational waves, particularly in the kilohertz band, play a crucial role in extracting information about such ultra-high densities. In recent years, several concepts for kilohertz-band gravitational wave detectors, such as Australia's NEMO, have been proposed to advance multi-messenger studies of high density astrophysical objects. KAGRA in Japan is also exploring upgrades aimed at enhancing high-frequency sensitivity, which could significantly improve sky localization accuracy and enable the detection of post-merger signals. This workshop aims to explore the transformative potential of high-frequency gravitational wave observations for multi-messenger astrophysics, with a focus on their implications for nuclear and neutron star physics. The workshop aims to spark dynamic discussions and cultivate new collaborations among participants through invited talks by leading experts and engaging poster presentations.

Venue: via Zoom

Event Official Language: English

Can social issues be solved by mathematical science!? - Between Mathematics and Entrepreneurship

February 1 (Sat) 13:00 - 17:00, 2025

We will be holding the 4th symposium exploring the potential of mathematical science research to address societal challenges. Over the past three years, we have focused on themes such as "Social Implementation of Mathematical Research—Challenges and Overcoming Them," "Connecting Corporate Issues with Mathematical Research," and "Mathematical Research in Companies." In recent years, there has been a global surge in support for startups leveraging cutting-edge scientific and technological innovations. However, there are relatively few cases where mathematical foundation technologies have led to the creation of startups. On the other hand, IT giants of the 21st century, such as Google, have built their success on mathematical technologies, demonstrating the high potential of mathematics as a core technology for startups. This year, we will hear from various organizations that support university-based startups, as well as researchers who have successfully launched their own ventures. Together with the participants, we aim to learn about the intersection of "mathematical foundation technologies" and "startups" and discuss strategies to bridge the gap between the two.

Venue: Hybrid Format (Noyori Conference Hall, Nagoya University and Zoom)

Event Official Language: Japanese

Seminar Series for Junior and Senior High School Girls: 'What Should Students Prepare for Their Future in the Age of AI?'

January 25 (Sat) 14:00 - 18:30, 2025

The RIKEN Center for Advanced Intelligence Project (AIP) and the Interdisciplinary Theoretical and Mathematical Sciences Program (iTHEMS) have jointly planned an event for junior and senior high school students interested in AI, mathematics, and information science. This event introduces the exciting research conducted by scientists in these fields. Join us to explore “The Future Built with AI” and discover what steps students can take now to prepare for the future. We look forward to your participation! For more details, please refer to the related links.

Venue: Nihonbashi AIP Center Open Space & Zoom (Hybrid Format)

Event Official Language: Japanese

Matter-Wave Interferometry in the Limit of High Mass and Internal Complexity, and the Relevance of Optomechanical Sources

December 16 (Mon) 10:00 - 11:00, 2024

Markus Arndt (Professor, University of Vienna, Austria)

The seminar will feature a lecture by Professor Markus Arndt from the University of Vienna. Following the lecture, starting at approximately 11:00 AM, Nobuyuki Matsumoto will give a brief introduction to his research and conduct a tour of his laboratory. Hosted by Gakushuin University Co-hosted by iTHEMS

Venue: Room 007, South Building 4, Gakushuin University

Event Official Language: English

Kyoto University SACRA-RIKEN iTHEMS Special Lecture by Prof. Tadashi Tokieda

March 28 (Thu) 13:30 - 16:30, 2024

Tadashi Tokieda (Professor, Department of Mathematics, Stanford University, USA)

This event will be conducted in Japanese.

Venue: Large Conference Room, The Kyoto University Tokyo Office

Event Official Language: Japanese

Can social issues be solved by mathematical science!? - Mathematical Research in Corporations

February 3 (Sat) 13:00 - 17:00, 2024

Continuing from the previous fiscal year, we will be hosting a symposium exploring the potential of solving societal issues through mathematical science research. In the past two years, the themes were "Attempts and Challenges" and "Connecting Corporate Issues and Mathematical Sciences." This year, we will focus on concrete examples under the title "Mathematical Research in Corporations" with the aim of introducing activities utilizing mathematics in the corporate sector. Currently, we are inviting speakers with diverse backgrounds, including researchers actively engaged in mathematical activities within corporations or those who have transitioned from corporate mathematical research to academic settings. We are particularly interested in learning about the experiences of individuals who have used mathematics in corporate settings. Additionally, there has been a growing trend in connecting activities of graduate students in mathematics with corporate endeavors. By sharing such initiatives with participants, we plan to conduct a panel session for exchanging opinions on the role of mathematical science in addressing societal issues through corporate collaboration in the future. We sincerely look forward to the active participation of corporate researchers and mathematicians who have an interest in these activities.

Venue: Hybrid Format (Noyori Conference Hall, Nagoya University and Zoom)

Event Official Language: Japanese

MCME SYMPOSIUM 2023

November 15 (Wed) - 16 (Thu) 2023

Kyosuke Adachi (Research Scientist, RIKEN Interdisciplinary Theoretical and Mathematical Sciences Program (iTHEMS))
Hiroshi Kokubu (Executive Vice-President, Kyoto University)
Masaru Hongo (Assistant Professor, Department of Physics, Faculty of Science, Niigata University)

"MCME SYMPOSIUM 2023" will be held at the Musashino Center of Mathematical Engineering (MCME), Musashino University. This symposium is free of charge and open to everyone. Colleagues of iTHEMS will also be speaking. Below is an excerpt from the program. Wednesday, November 15, 11:20 - 12:30 Kyosuke Adachi Wednesday, November 15, 16:20 - 17:30 Hiroshi Kokubu Thursday, November 16, 10:00 - 11:10 Masaru Hongo Registration is open until November 14. Please register from the related links below. Organized by Musashino Center of Mathematical Engineering (MCME), Musashino University Co-organized by RIKEN Interdisciplinary Theoretical and Mathematical Sciences Program (iTHEMS)

Venue: Hybrid Format (Room 301, Building 5, Ariake Campus, Musashino University and Zoom)

The 4th "Medicine and Mathematics" Workshop

September 29 (Fri) - 30 (Sat) 2023

We will have the 4rd workshop on "Medicine and Math" in Sendai (hybrid style) on Sep.29-30, 2023. Please join if you are interested in this interdisciplinary subject. Most of the talks are in Japanese except for session 4. For more information and registration, please visit the related links. For more information and registration, please visit the related links. Co-organized by: Center for Integrative Medicine and Physics, Kyoto University Institute for Advanced Study (KUIAS) Center for Science Adventure and Collaborative Research Advancement (SACRA), Kyoto University Tohoku Forum of Creativity, Tohoku University RIKEN Interdisciplinary Theoretical and Mathematical Sciences Program (iTHEMS)

Venue: TOKYO ELECTRON House of Creativity, Katahira Campus, Tohoku University / via Zoom

NU-Q-iTHEMS-YITP Lecture: Applications of Quantum Computation in Quantum Field Theory

July 6 (Thu) - 7 (Fri) 2023

Masazumi Honda (Assistant Professor, Yukawa Institute for Theoretical Physics, Kyoto University)

This lecture aims to provide an introductory explanation of the application of quantum computation in numerical simulations of quantum field theory. We will begin by covering the fundamental aspects of quantum computation, followed by a discussion on its application to simulating spin systems. Subsequently, we will delve into introductory explanations of continuous field quantum theory and lattice field quantum theory, and discuss their simulation methods. Additionally, practical exercises utilizing IBM Qiskit for quantum simulations will be conducted. Important Notice for Participants: Please note that loaner laptops for the practical exercises will not be provided, so please bring your own laptops. Prior to the lecture, please ensure that you have set up your environment to use Jupyter Notebook, for example, by installing Anaconda. Organizers: Quantum Research Center (NU-Q), Niigata University / Yukawa Institute for Theoretical Physics (YITP), Kyoto University Co-organizer: RIKEN Interdisciplinary Theoretical and Mathematical Sciences Program (iTHEMS)

Venue: #A317, Building A, Faculty of Science, Niigata University / via Zoom

Event Official Language: Japanese

g-RIPS-Sendai 2023

June 19 (Mon) - August 8 (Tue) 2023

The Research in Industrial Projects for Students (RIPS) program has been held at the Institute for Pure & Applied Mathematics (IPAM) of the University of California, Los Angeles. In 2018, the Advanced Institute for Materials Research (AIMR) at Tohoku University in Sendai launched the g-RIPS-Sendai program in collaboration with IPAM, targeting graduate-level students in mathematical science and related disciplines. Participants from the U.S. and Japan will work on cross-cultural teams on research projects designed by industrial partners. The projects are expected to be of great interest to the partners and offer stimulating challenges to students. For more information on this year's g-RIPS-Sendai 2023, please visit the program website at the related link. Organizers: Research Alliance Center for Mathematical Science (RACMaS), Tohoku University Tohoku Forum for Creativity (TFC), Tohoku University Advanced Institute for Materials Research (AIMR), Tohoku University In cooperation with the following organizations: RIKEN Interdisciplinary Theoretical and Mathematical Sciences Program (iTHEMS) Institute for Pure & Applied Mathematics (IPAM), UCLA

Venue: Advanced Institute for Materials Research (AIMR), Tohoku University

Exploring GPT’s Influence on Natural Science and Mathematics

May 17 (Wed) 10:00 - 15:00, 2023

We are organizing a workshop to explore the application of ChatGPT in natural sciences, with a focus on theoretical physics and mathematics. Advances in GPT-4 and plugin technology are expected to bring about transformative changes in the way research is conducted. We will investigate the potential for another shift in research methodology following the advent of computers. Expert-led lectures on large language models (LLMs/ChatGPT) will also be conducted. We aim to deepen the discussion on the effective utilization of LLMs as tools to support the research of physicists and mathematicians. This workshop will be held in a hybrid format, combining online streaming with in-person presentations, to accommodate a larger number of participants. In addition to the lectures, short talks and discussions will be held entirely offline. The target audience is mainly students and researchers in the natural sciences, but please note that there will be a limit to the number of in-person attendees. The aim of this event is to provide a forum for researchers to engage in earnest discussions. Those who do not align with the objectives of this workshop are kindly asked to refrain from participating. We look forward to this opportunity to consider, together with all of you, new research methods and perspectives in the fields of theoretical physics and mathematics in the natural sciences, utilizing ChatGPT. (The above text was created by modifying the text generated by Chat-GPT and GPT-4.) All talks will be delivered in Japanese.

Venue: #435-437, 4F, Main Research Building (Main Venue) / via Zoom

Event Official Language: Japanese

Spring Workshop on Quantum Gravity

April 26 (Wed) - 28 (Fri) 2023

This is co-hosted by iTHEMS and NCTS, and is also the first of Quantum Gravity Gatherings. What is space-time? How did the universe begin? Various approaches exist toward theories of quantum gravity that can answer such fundamental questions. Each approach has its own strengths and weaknesses and should capture, at least partially, some essential aspect of quantum gravity. Then, what are the general properties (if any) of the quantum nature of gravity independent of the details of such approaches? As the main speaker, we have asked Hikaru Kawai to give an intensive talk approaching this question from both general and specific arguments in a style consistent with the concept of Quantum Gravity Gatherings. We hope that the younger generation will experience his powerful arguments based on his experience and deep insights. This workshop is intended to be a lively and participatory event, not just a listening experience. For this reason, the number of participants will be limited to about 30 with priority given to graduate students and young post-docs; the intensive talk will be given in a face-to-face blackboard style (in English, no online streaming) to allow for informal and lively Q&A discussions. In addition, there will be sessions where any participant can give a short talk on any topic of his/her choice. Through these, all the participants will discuss the above question from various angles, and the young generations in Japan and Taiwan will stimulate each other and start new exchanges.

Venue: #435-437, 4F, Main Research Building

Event Official Language: English

An overview on the nuclear equation of state studied from ground and collective excited state properties of nuclei

April 12 (Wed) 13:30 - 15:00, 2023

Xavier Roca-Maza (Associate Professor, Department of Physics, University of Milan, Italy)

This contribution reviews a selection of available constraints to the nuclear equation of state (EoS) around saturation density from nuclear structure calculations on ground and collective excited state properties of atomic nuclei [1]. It concentrates on predictions based on self-consistent mean-field calculations, which can be considered as an approximate realization of an exact energy density functional (EDF). Mostly, EDFs are currently derived from effective interactions commonly fitted to nuclear masses, charge radii and, in many cases, also to pseudo-data such as nuclear matter properties. Although in a model dependent way, EDFs constitute nowadays a unique tool to reliablyand consistently access bulk ground state and collective excited state properties of atomic nuclei along the nuclear chart as well as the EoS. The impact on the EoS of the new CREx [2] and PREx [3] measurments of the parity violating asymmetry (ground state observable) in 48Ca and 208Pb, respectively, will be also discussed [4,5] and compared to previously presented results on collective excitations. As the main conclusion, the isospin dependence of the nuclear EoS around saturation density and, to a lesser extent, the nuclear matter incompressibility remain to be accurately determined. Experimental and theoretical efforts in finding and measuring observables specially sensitive to the EoS properties are of paramount importance, not only for low-energy nuclear physics but also for nuclear astrophysics applications.

Venue: 2F Large Meeting Room, RIBF Building, RIKEN Wako Campus (Main Venue) / via Zoom

Event Official Language: English

Interdisciplinary Science Conference in Okinawa (ISCO 2023)

February 27 (Mon) - March 3 (Fri) 2023

The scientific method of studying the natural world has persisted over the centuries. The key to its longevity and progression lies in sharing and building upon accumulated knowledge. Physics, which explores the origin of the universe and matter; biology, which studies living organisms, and their functions and evolution; and medicine, which explores health based on the structure and function of living organisms: all have made enormous advancements that impact all aspects of our lives. As the scientific study progresses, however, additional challenges have arisen which are increasingly difficult to solve. Many of the challenges that humanity faces are in achieving sustainable development. These include environmental changes due to climate change, food crises caused by the gap between population growth and food production, and pandemics caused by the spreading of resistant bacteria and viruses. To rise to these new challenges, it is important to reassess the issues from a broader perspective: to combine the knowledge and methods of different scientific fields and to look for new approaches that can bridge the boundaries and work across multiple fields The purpose of ISCO 2023 is to bring together leading researchers in their respective fields, explore methods for solving issues through the fusion of different fields, and form a new network of researchers. The workshop will bring together speakers from Japan and abroad in the fields of space science, particle and nuclear physics, quantum computing, life sciences, and medicine to discuss the challenges they face and the latest advancements in their respective fields. We call for presentations from fields related to those subjects mentioned above and on the sustainable development of humankind. In addition, we plan to hold a poster session to facilitate a wide range of discussions. We hope that the knowledge gained at this workshop will lead to the creation of new research fields that will not only advance basic science but will also help solve the various new challenges that humanity faces.

Venue: OIST Auditorium / via Zoom

Event Official Language: English

Connecting the hierarchies: from cosmos to life

February 20 (Mon) 10:00 - 16:45, 2023

Yuki Yokokura (Senior Research Scientist, RIKEN Interdisciplinary Theoretical and Mathematical Sciences Program (iTHEMS))
Etsuko Itou (Senior Research Scientist, RIKEN Interdisciplinary Theoretical and Mathematical Sciences Program (iTHEMS))
Catherine Beauchemin (Deputy Program Director, RIKEN Interdisciplinary Theoretical and Mathematical Sciences Program (iTHEMS))

As each research field in modern science has matured and become more sophisticated and deepened, it has also created the problem that it has become too fragmented from the perspective of the field as a whole. On the other hand, looking at individual research themes, research that connects different hierarchical structures, such as cosmogenesis and particle theory, neutron stars and nuclear theory, large-scale structure of the universe and formation of galaxies, stars, and planets, turbulent phenomena over a wide range of scales, life and non-equilibrium phenomena, etc., is progressing, and efforts to understand physical phenomena from an integrated perspective is spreading. The term "hierarchy" can also be interpreted as a hierarchy of theories, different principles and perspectives. Therefore, in this TJR workshop, we invite relevant lecturers from external institutes to give talks focusing on how they are striving to link different hierarchies in their respective research fields, with the aim of broadening our research perspectives and inspiring future research. Of course, the purpose is also to inform and inspire the younger generation about cross-disciplinary research topics.

Venue: Nambu Hall, Toyonaka Campus, Osaka University / via Zoom

Can social issues be solved by mathematical science!? - Connecting Corporate Issues and Mathematical Sciences -

January 7 (Sat) 13:00 - 17:00, 2023

Continuing from last year, we will hold a symposium to explore the possibility of solving social issues through mathematical research. Last year, under the theme of "Social Implementation of Mathematical Research!? - Attempts and Challenges -", we held talks by mathematical scientists working on mathematical problems extracted from corporate issues, and saw that efforts to address issues of interest at the individual researcher level are becoming more active. This year, under the broader theme of "Connecting" mathematical scientists and companies, we will introduce not only researchers who are strongly promoting joint research with companies, but also activities of companies who are collaborating with mathematical scientists from the standpoint of companies. We would like to organize a panel session to share with the participants not only the results of their activities but also the difficulties of the collaboration and the exchange of opinions on how to solve the problems. We are sincerely looking forward to the active participation of corporate researchers and mathematical scientists who are interested in such activities.

Venue: Hybrid Format (Noyori Conference Hall, Nagoya University and Zoom)

Event Official Language: Japanese

MCME SYMPOSIUM 2022

November 16 (Wed) - 17 (Thu) 2022

Takemasa Miyoshi (Team Leader, Data Assimilation Research Team, RIKEN Center for Computational Science (R-CCS))
Hidetoshi Taya (Special Postdoctoral Researcher, RIKEN Interdisciplinary Theoretical and Mathematical Sciences Program (iTHEMS))
Hidetoshi Nishimori (Specially Appointed Professor, Tokyo Institute of Technology)

"MCME SYMPOSIUM 2022" will be held at the Musashino Center of Mathematical Engineering (MCME), Musashino University. This symposium is free of charge and open to everyone. Colleagues of iTHEMS will also be speaking. Below is an excerpt from the program. Wednesday, November 16, 13:30 - 14:40 Takemasa Miyoshi Thursday, November 17, 10:00 - 11:10 Hidetoshi Taya Thursday, November 17, 14:50 - 16:00 Hidetoshi Nishimori Registration is open until November 14. Please register from the related links below. Organized by Musashino Center of Mathematical Engineering (MCME), Musashino University Co-organized by RIKEN Interdisciplinary Theoretical and Mathematical Sciences Program (iTHEMS)

Venue: Hybrid Format (Room 301, Building 5, Ariake Campus, Musashino University and Zoom)