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Farewell message from Yaokun Lei

Our colleague Yaokun Lei will move on to a new career as associate research fellow at Shenzhen Bay Laboratory, China as of November. 11, 2024. We all will miss him and wish him the best of luck in his latest endeavor. Here is a message from Yaokun Lei: <i>I joined iTHEMS last August. Although it’s a short time, it has been a truly enriching experience to be a part of iTHEMS. The support and collaborative spirit here have been invaluable, and I am especially grateful for the guidance and help from Hatsuda-san and Sugita-san, whose encouragement has greatly impacted this journey. I am thankful for the friendships and knowledge shared, and as I step forward, I carry with me not only the insights from my research but also the inspiration from our exchanges. I hope our paths cross again in future collaborations. Thank you all for everything, and wishing you continued success and discoveries.</i>

2024-11-12
New Perspectives from the Intersection of Mathematics and Physics - Yuto Moriwaki

When people think of research in quantum field theory, most imagine physicists. However, Special Postdoctoral Researcher Yuto Moriwaki is a mathematician. In this interview, we asked Moriwaki about the allure and challenges of working across the fields of mathematics and physics. Please see the full article via the related link.

2024-10-23
Discovery of a Sustained Magnetic Flow in Ultracold Atomic Gases

An international research group, including Yuta Sekino (Postdoctoral Researcher, iTHEMS / Postdoctoral Researcher, Nonequilibrium Quantum Statistical Mechanics RIKEN Hakubi Research Team) has discovered a mechanism that generates a long-lasting magnetic flow using ultracold atomic gases. This research result is expected to contribute to the realization of quantum simulators, which are essential for the development of highly efficient next-generation magnetic memory. For further details, please refer to the related link.

2024-10-22
Creation of the Quantum Universe and Precise Calculation of the Wave Function of the Universe

In modern cosmology, the idea that the universe was created from nothing through quantum effects has been a topic of active research. However, a long-standing debate has persisted regarding which of two prominent hypotheses—the no-boundary proposal or the tunneling proposal—is correct. A research team, including Hiroki Matsui (Postdoctoral fellow, Yukawa Institute for Theoretical Physics), Kazumasa Okabayashi (Postdoctoral fellow, Yukawa Institute for Theoretical Physics), Masazumi Honda (Senior Research Scientist, RIKEN), and Takahiro Terada (Research Assistant Professor, Nagoya University), has made significant progress in this debate by calculating the wave function of the universe from first principles, without the need for arbitrary assumptions about either proposal. Previous analyses left mathematical ambiguities unresolved, but this team eliminated those ambiguities using a method called resurgence theory. Their calculations rigorously demonstrated, under certain assumptions, that the wave function of the universe aligns with predictions from the tunneling proposal, not the no-boundary proposal. This result is a giant step forward in resolving the longstanding debate between these two hypotheses. For more details, please refer to the Kyoto University press release via the related links.

2024-10-17
Report on the induction ceremony of American Academy of Arts and Sciences

Tetsuo Hatsuda attended the induction ceremony of the American Academy of Arts and Sciences [1], held in Cambridge, Massachusetts, from September 29 to October 1, 2024, as a newly elected International Honorary Member (HIM). This year, 250 new members were inducted, including 25 HIMs [2], across various fields such as Mathematical and Physical Sciences, Biological Sciences, Social and Behavioral Sciences, Humanities and Arts, and Leadership, Policy and Communications. The ceremony began with a gathering of new members at the House of the Academy [3]. The formal induction took place on September 30 at Sanders Theatre, Memorial Hall at Harvard University [4], starting at 3 p.m. During the ceremony, each inductee was called to the stage individually to sign the Academy members’ book. In addition to the induction ceremony, there were receptions on September 29 and 30. The event concluded with a special lecture titled "Memory is about your future – what we think we become," delivered by André Fenton. In the photograph, Tetsuo Hatsuda is seen on the left signing the Academy's book. On the right, he is pictured conversing with Bonnie Fleming [5], a fellow inductee in physics and a neutrino experimentalist from Fermilab. Throughout the meeting, Tetsuo enjoyed engaging in conversations not only with fellow physicists but also with researchers from the social sciences and humanities.

2024-10-09
Presentation of iTHEMS outreach at NuFACT conference

iTHEMS is a fantastic environment in which we conduct interdisciplinary research daily. Along with our research activity, a variety of outreach activities have been conducted so far. Tomoya Nagai (Coordinator, iTHEMS) presented this special environment and its outreach activity at the NuFACT 2024 conference. At the conference, a session for Inclusion, Diversity, Equity, Education, and Outreach (IDEEO) was composed. The session itself was organized so that we could visualize diversity in terms of speaker's and convener's properties. It provided us with a good opportunity to know IDEEO-related activities all over the world, which can be a chance to recognize and reconsider the issue around to achieve "good environments for everyone". One special example of the iTHEMS outreach was the "Journalist in residence" program. The uniqueness of the activity caught significant attention from the participants of the conference. Also, "Mathematics Connecting to the World: One S&T poster for Every Household" seemed to be intriguing. Although we had only a limited time for this exhibition and discussion, Nagai's attendance brought the conference a fresh view of the outreach activity as well as the achievements of the interdisciplinary and diverse environments. iTHEMS can be so influential to our community in multiple contexts!

2024-10-08
RIKEN - LBNL Workshop on Quantum Information Science on September 3-6, 2024

On Sep. 3 (Tue) - 6 (Fri), RIKEN - LBNL Workshop on Quantum Information Science was held at Lawrence Berkeley National Laboratory (LBNL). The workshop was co-hosted by RIKEN-iTHEMS and LBNL and sponsored by RIKEN Quantum, with 32 and 40 participants from Japan and USA, respectively. This was the second in-person workshop by RIKEN and LBNL on quantum information science since the first was held at LBNL in January 2019 before the Covid-19 pandemic. The purpose of the workshop was to bring together researchers worldwide to discuss and collaborate on the latest developments in quantum technologies and quantum computing including algorithms, hybrid quantum-classical computing, error mitigation, and applications in physics and chemistry. There were 36 talks and 4 poster presentations during the entire four days. In the afternoons of the second and third days, in addition to tours of LBNL's Advanced Quantum Testbed (AQT) and National Energy Research Scientific Computing Center (NERSC) facilities, special sessions delved into discussions on several focus areas and provided networking opportunities for future collaborations.

2024-10-02
Farewell message from Eiji Inoue

Our colleague Eiji Inoue will move on to a new career as an assistant professor at Kyoto University as of Oct. 1, 2024. We all will miss him and wish him the best of luck in his latest endeavor. Here is a message from Eiji Inoue: <i>I spent three and a half years in iTHEMS as an SPDR on math. I would like to thank the program director and assistants for their mindful support over these three and a half years. I also wish to thank iTHEMS members for discussion on many occasions. These years I spent in iTHEMS were invaluable for me. Among all, the best experience for me was that I could gradually get a feeling on "physics in the real world" not only mathematical structure of physics, from the choice of words physicists use in daily discussion. In these casual discussions, I could also try if my understanding of physics are correct. I also enjoyed playing quantum computers. I think it was impossible to experience without this tolerant environment of iTHEMS; indeed, it just started from a casual conversation with the director. It was the first time I experienced quantum phenomena, especially quantum entanglement, in the real world where I exist. This may sound a little strange, but I feel like I haven't had that feeling of interest in how the real world works in a long time. While I was going through these experiences like a newborn child, as a mathematician, I could finally achieve my original project on Perelman entropy in the last half year during my visits to Cambridge, Montreal and Aarhus. There are still many thigs to do, but this is certainly the foundation of this new theory. One regret is that I could not finish writing a paper on this result while enrolled at iTHEMS. I'll be an assistant professor at Kyoto University (Department of Math) from October. I welcome people from iTHEMS to come to Kyoto and discuss. I will also ask iTHEMS for help. See you again! </i>

2024-09-27
Farewell message from Kazuki Kannaka

Our colleague Kazuki Kannaka will move on to a new career as an assistant professor at Kanazawa University as of Oct. 1, 2024. We all will miss him and wish him the best of luck in his latest endeavor. Here is a message from Kazuki Kannaka: <i>At iTHEMS, thanks to the support from Hatsuda-san, Tada-san, Tsuboi-sensei, and all the assistants, I was able to focus on my research in a wonderful environment. During this period, I made several discoveries that were interesting at least to me. Also, discussing with researchers from other fields at iTHEMS was exciting. I am especially grateful to Namba-san and Iritani-san for providing the opportunity for such discussions. I look forward to continuing our research exchanges. Thank you!</i>

2024-09-24
Energy Transmission Requires Information: Approaching the Physics of Boundary Interfaces

A research group, including Yuya Kusuki (Associate Professor, Institute for Advanced Study, Kyushu University / Visiting Scientist, iTHEMS), has demonstrated a clear inequality in 2-dimensional conformal quantum field theory. The inequality links the energy transmission rate, the information transmission rate, and an indicator of the size of the Hilbert space in quantum field theory (specifically, the growth rate of the number of states at high energy) as follows: (energy transmission rate) ≤ (information transmission rate) ≤ (indicator of the size of the Hilbert space). For more details, please refer to Kyushu University's website via the related links below.

2024-09-20

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Interdisciplinary Theoretical and Mathematical Sciences Program (iTHEMS) is an international research program at RIKEN. It facilitates close collaborations among researchers from different disciplines in theoretical, mathematical and computational sciences. The ultimate goal of iTHEMS is to unravel the mystery of the Universe, matter, and life, as well as to solve key problems in modern society through interdisciplinary approaches.

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Program Director: Tetsuo Hatsuda

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