理化学研究所数理創造研究センター (iTHEMS) | iTHEMS

Featured News

Using chaos and symmetry to bootstrap quantum gravitational wormholes

An international research collaboration between Gabriele Di Ubaldo (RIKEN-Berkeley Center at UC Berkeley and RIKEN iTHEMS), Jan Boruch (University of California, Berkeley, US), Felix M. Haehl (University of Southampton, UK), Eric Perlmutter (Université Paris-Saclay and Institut des Hautes Études Scientifiques, France), and Moshe Rozali (University of British Columbia, Canada) published the new study in <em>Physical Review Letters</em>. Random matrix theory provides a universal description of chaos in quantum systems, capturing statistical patterns among energy levels without requiring knowledge of microscopic details. The new challenge addressed is its extension to 2D Conformal Field Theories and their holographically dual 3D quantum gravity via the AdS₃/CFT₂ correspondence. In the AdS₃/CFT₂ correspondence, quantum gravity in a three-dimensional negatively curved spacetime is encoded in a two-dimensional conformal field theory on its boundary. The key difference is <strong>modular invariance</strong>, a symmetry stating that a theory on a 2D torus is invariant under modular transformations, which imposes stringent constraints and a rigid mathematical structure, seemingly incompatible with quantum chaos and random matrix theory. Building on the 2023 work of Di Ubaldo and Perlmutter, “AdS₃/RMT₂ duality”, the researchers developed a general, nonperturbative framework called RMT₂ that uplifts the correlations of any random matrix model into fully modular-invariant quantities. The team then used RMT₂ to predict quantum amplitudes for 3D wormholes with multiple torus-shaped boundaries. A wormhole is a tunnel-like geometric connection between otherwise separate regions or boundaries of spacetime. While it is not a shortcut for interstellar travel as in sci-fi movies, it encodes deeply quantum information about gravity and black holes. For the three-boundary wormhole, the team also performed a gravity calculation that agrees with the RMT₂ prediction. By turning the earlier AdS₃/RMT₂ proposal into a general framework, the study advances a research direction that Gabriele helped pioneer and provides a new tool for probing black-hole microstates and, in the near future, solving AdS₃ quantum gravity. For further details, please see the article in <em>Physical Review Letters</em>.

2026-08-07
Riccardo Muolo Awarded Third Place at Falling Walls Lab Tokyo 2026

Riccardo Muolo awarded 3rd Place at Falling Walls Lab Tokyo, Japan Riccardo Muolo (Special Postdoctoral Researcher, Division of Fundamental Mathematical Science, iTHEMS) took part in the Falling Walls Lab Tokyo, Japan, held on 28 July 2026 at Shibuya Sakura Stage, and was awarded 3rd Place by the jury. The Falling Walls Lab is an international pitch and science-communication competition hosted by the Falling Walls Foundation, a Berlin-based non-profit founded in 2009 on the twentieth anniversary of the fall of the Berlin Wall. The Foundation channels the spirit of that night to ask a recurring question — which are the next walls to fall in science and society — and works to make breakthrough ideas accessible across borders and disciplines. Open to students and early-career professionals of all disciplines and nationalities, the Lab invites participants to pitch their research, business model, or innovative idea in just three minutes, in front of their peers and a jury from academia and business. Academic institutions around the world are invited to host their own Falling Walls Lab and send their winners to the Falling Walls Lab Finale in Berlin, where the Finalists compete for the title of Breakthrough Winner in the Emerging Talents category and the chance to pitch again on the main stage of the Falling Walls Science Summit. This year’s Tokyo edition was organized by EURAXESS Japan, the German Centre for Research and Innovation (DWIH) Tokyo, and Tobitate! Japan. Riccardo’s research covers nonlinear dynamics on networks and higher-order structures, synchronization, Turing pattern formation, and the control of dynamical systems — exactly the kind of cross-disciplinary work the Falling Walls Lab is designed to showcase. Distilling it into a compelling three-minute pitch and earning recognition among a strong international field of participants is a fine achievement. Congratulations, Riccardo!

2026-08-07
原子検出回数の異常ゆらぎと普遍性の発見

大阪公立大学大学院理学研究科の山本和樹講師と、理化学研究所開拓研究所の濱崎立資理研白眉研究チームリーダー（理化学研究所数理創造研究センター上級研究員）は、多数の原子からなる量子多体系を連続的に測定した際に、原子の検出回数のゆらぎが、測定の強さによって大きく変化することを理論的に明らかにしました。測定が弱い場合には、原子の検出回数は標準的なゆらぎを示す一方で、測定が強い場合には、通常よりも大きな「異常ゆらぎ」が現れることを発見しました。詳細は大阪公立大学のホームぺ―ジをご覧ください。

2026-08-06
2026 iTHEMS Visit by the National Sun Yat-sen University, Taiwan

On June 25, a group of 3 professors and 13 students from National Sun Yat-sen University, Taiwan, visited RIKEN . The purpose of the visit was to immerse the students in RIKEN’s multidisciplinary research environment and introduce them to stateoftheart scientific methodologies. It also aimed to inspire their future research careers while exploring opportunities for academic exchange and longterm collaboration between both institutions. First, the group visited RIKEN Nishina Center for Accelerator-Based Science, hosted by Dr Claudio Santonastaso & Dr Seiya Sakai. Next visit was RIKEN Center for Interdisciplinary Theoretical and Mathematical Sciences (iTHEMS), hosted by Dr. Gen Kurosawa. Last visit was RIKEN Center for Quantum Computing, hosted by Dr. Franco Nori. Gen Kurosawa, Senior Research Scientist, introduced iTHEMS’s interdisciplinary research environment and explained how mathematical methods from physics can be applied to important questions in biological clocks, leading to testable predictions that are verified experimentally.

2026-07-29
Farewell message from Puttarak Jai-akson

Our colleague, Puttarak Jai-akson, will be joining the Graduate School of Science, Kyoto University, as a Program-Specific Researcher, starting in August 2026. We will all miss him and wish him every success in this exciting new chapter. Here is a message from Puttarak: <i>I would like to share that I will be leaving my position as a Postdoctoral Researcher at iTHEMS.</i> <i>I joined iTHEMS in November 2022, and after nearly four wonderful years, I will be moving to a new position as a Researcher at Kyoto University, starting in August 2026.</i> <i>During my time at iTHEMS, I greatly enjoyed the open, friendly, and interdisciplinary research environment. The opportunity to interact with researchers from diverse fields has broadened my perspective, inspired many new ideas, and significantly enriched my research. I am deeply grateful to all the members of iTHEMS for their support, encouragement, and the many enjoyable discussions we have shared. I would also like to express my heartfelt thanks to our wonderful iTHEMS Assistants, whose kindness, professionalism, and constant support made my time at iTHEMS all the more enjoyable.</i> <i>Although I am leaving my full-time position, I am pleased to continue my affiliation with iTHEMS as a Visiting Scientist. I sincerely hope to continue our discussions and collaborations in the future.</i> <i>If you happen to visit Kyoto University, please don't hesitate to let me know. I would be very happy to catch up and continue our conversations.</i> <i>Thank you all very much for everything. It has been a privilege to be part of iTHEMS, and I wish everyone continued success.</i>

2026-07-24
2026 iTHEMS Visit by the University of California San Diego Global Seminar Program

On July 8, Dr. Stanley Lo, Teaching Professor in the Department of Cell and Developmental Biology at the School of Biological Sciences, UCSD, visited iTHEMS together with 24 undergraduate students. The purpose of the visit was to learn about iTHEMS and its research activities while supporting the students’ learning about human diversity and the relationship between science and society. Thomas Hitchcock, Research Scientist at iTHEMS, hosted the lecture. He introduced his academic and professional background and presented his current research on evolution, ecology, and genetics.

2026-07-16
自然法則に現れる「自由に選べる数」の由来に迫る－量子重力における自由パラメータの謎に新たな手掛かり－

楠亀裕哉 iTHEMS客員研究員(本務: 九州大学高等研究院准教授）を含む国際共同研究グループは、2つの共形場理論を「界面」でつなぐ状況を解析しました。その結果、界面をわずかに動かしたときの応答を適切に取り出すと、2つの理論の違いを生む局所的な演算子が得られることを示し、それを具体的に構成する方法を与えました。今回の成果は、「量子重力には外から自由に選べる連続パラメータが存在しない」という予想を裏付けるものとなっており、量子重力の根本問題の理解につながると期待されます。詳細は九州大学のプレスリリースをご覧ください。

2026-06-24
The First RIKEN Quantum International Workshop on Frontiers of Quantum Computing Applications and Quantum-HPC Integration on May 25-26, 2026

The First RIKEN Quantum International Workshop on Frontiers of Quantum Computing Applications and Quantum–HPC Integration was held from May 25 to 26 at the Large Conference Room on the 2nd floor of the Administrative Headquarters, RIKEN Wako Campus. The workshop featured an entirely invited program, consisting of 13 plenary presentations (40 minutes each) and 9 highlight presentations (20 minutes each). The presentations covered a broad range of fields—including quantum chemistry, life sciences, condensed matter physics, atomic physics, and high-energy physics—with a primary focus on the theme of quantum–HPC hybrid integration. With more than 130 registered participants, each presentation was followed by lively and engaging discussions. Furthermore, the networking reception held on the evening of the first day was well-attended, fostering active interaction and collaboration among researchers from universities, national research institutes, and private industries. This workshop is expected to drive further advancements in quantum computing through quantum–HPC hybrid integration. Reported by Shinichiro Fujii

2026-06-11
平島敬也基礎科学特別研究員が「HPCIソフトウェア賞開発部門賞優秀賞」を受賞

平島敬也基礎科学特別研究員が、一般社団法人HPCIコンソーシアムが主催する「HPCIソフトウェア賞開発部門賞優秀賞」を受賞しました。 HPCIソフトウェア賞は、計算科学分野の発展に貢献した優れたソフトウェアの開発者や普及活動に携わる若手研究者・団体を表彰する賞です。開発部門賞では、大規模計算などの計算科学において特に有益なソフトウェアの開発が評価されます。今回の受賞は、「AIを組み合わせた銀河シミュレーションコード『ASURA-FDPS-ML』の開発」に対して授与されました。ASURA-FDPS-MLは、銀河形成・進化の数値シミュレーションと機械学習技術を組み合わせることで、大規模な宇宙・銀河シミュレーションの効率化や高度化を目指した研究開発成果です。本受賞は、計算科学とAI技術を融合した先進的な研究開発が高く評価されたものです。

2026-06-03
森川億人基礎科学特別研究員が「第21回素粒子メダル奨励賞」を受賞

森川億人基礎科学特別研究員が、2026年度第21回素粒子メダル奨励賞を受賞しました。本賞は、素粒子論分野において優れた研究業績を挙げた若手研究者に授与される賞です。受賞対象となった論文では、量子力学や場の理論において重要な役割を果たす共鳴状態について、厳密WKB法に基づく統一的な解析枠組みを構築しました。従来は別々の手法として発展してきたZel'dovich正則化、complex scaling法、rigged Hilbert spaceによる記述を非摂動論的な観点から結び付けることで、共鳴状態を統一的に理解するための基盤を与えました。さらに、具体的な可解模型を用いてその有効性を示し、散乱理論や非エルミート量子系、リサージェンス理論をつなぐ新たな視点を提示したことが高く評価されました。本研究は、共鳴状態を含む量子論の基礎的理解を深めるとともに、今後、より一般の量子系や場の理論、量子重力における非摂動的構造の解析への発展が期待されています。

2026-06-03

Videos

数理創造研究センター（RIKEN Center for Interdisciplinary Theoretical and Mathematical Sciences, 略称 iTHEMS アイテムス）は、理論科学・数学・計算科学の研究者が分野の枠を越えて基礎研究を推進する、国際研究拠点です。2025年4月1日にプログラムからセンターへと組織改編されました。iTHEMSでは、「数理」を軸とする分野横断的手法により、宇宙・物質・生命の解明や、社会における基本問題の解決を目指しています。

iTHEMSについて

磯暁の写真

センター長: 磯暁

Upcoming Events

イベント一覧イベントカレンダー

Opportunities

採用情報一覧

Latest News

ニュース一覧

Upcoming Visitors

来訪中

Yang-Yang Tan

東京大学大学院理学系研究科知の物理学研究センター博士研究員

期間: 2026年5月1日(金) - 2027年4月30日(金)

来訪場所: 理化学研究所和光キャンパス研究本館
来訪中

Victor Kawasaki-Borruat

Doctoral Student, Doctoral Program in Electrical Engineering, École Polytechnique Fédérale de Lausanne (EPFL), Switzerland

期間: 2026年8月3日(月) - 9月4日(金)

来訪場所: 理化学研究所和光キャンパス研究本館
明日来訪

舘石和香葉

北海道武蔵女子大学助教

期間: 2026年8月18日(火) - 21日(金)

来訪場所: 理化学研究所和光キャンパス研究本館
Bowen Yang

Postdoctoral Fellow, Harvard University, USA

期間: 2026年8月29日(土) - 9月11日(金)

来訪場所: 理化学研究所和光キャンパス研究本館

ビジター一覧