RIKEN Center for Interdisciplinary Theoretical and Mathematical Sciences

International and Interdisciplinary Collaboration at the RIKEN-Berkeley Center - Yuuka Kanakubo

"I’m leaving for the U.S. tomorrow," says Yuuka Kanakubo, who joined iTHEMS in October 2024 as a Postdoctoral Researcher and RIKEN-Berkeley Fellow. Her specialty is elementary particle and nuclear theory. She will be conducting research during a long-term stay at the RIKEN-Berkeley Center, iTHEMS' satellite office. "This position is perfect for me," Kanakubo says. We asked her about her journey so far and what makes this opportunity ideal. Please see the full article via the related link.

2025-05-22

Yoshimasa Hidaka received the 25th Soryushi Medal for his unified description of the Nambu-Goldstone theorem

Yoshimasa Hidaka, our Deputy Director, is awarded 25th SORYUSHI MEDAL (Paricle Physics Medal) from Japanese Particle Theory Community. The title of the achievement is “Unified Description of the Nambu-Goldstone Theorem”. The award will be presented at the 80th Annual Meeting of the Physical Society of Japan, to be held at Hiroshima University from September 16 to 19, 2025. Congratulations!!

2025-05-22

Haruki Emori received the “Second Prize”

Our colleague Haruki Emori (Junior Research Associate, iTHEMS) has received the “Second Prize’” in the Poster Session for the Quantinuum 2025 May Training Session. The outstanding presentation poster is entitled “Quantum algorithm for implementing arbitrary quantum instruments based on parameterized quantum circuits”. Congratulations, Haruki!

2025-05-22

Looking for “Overlap” to Connect - Akihisa Yamamoto

"I have always walked along the boundaries between different fields," says Research Scientist Akihisa Yamamoto. Currently, he is focusing on the interdisciplinary field between medicine and mathematics, seeking to identify patterns in doctors' experiential knowledge, translating them into mathematical models, and applying them to deepen our understanding of biological phenomena while contributing to clinical practice. We spoke with him about the encounters that led him to this path, as well as the unique challenges and excitement of working at the intersection of disciplines. Please see the full article via the related link.

2025-05-20

Utilizing Every Possible Method to Challenge the Ultimate Goal - Masazumi Honda

What are the fundamental building blocks of the universe? What is the ultimate physical law that govern the universe? How did the universe begin? Theoretical high energy physics, which seeks to answer these profound questions, is the main research field for Masazumi Honda. We spoke with Honda about his journey to iTHEMS, the breadth of his research approaches and disciplines, and his recent research on applying quantum computers to high energy physics. Please see the full article via the related link.

2025-05-15

iTHEMS x academist online event was held on April 19, 2025

iTHEMS held an online lecture event for the general public with the help of Academist Inc., on April 19, 2025. This year’s speakers were Yuuka Kanakubo, Kan Kitamura, Leo Speidel, and Yuki Yokokura, who delivered clear and easy-to-understand lectures that even middle school students could comprehend. Each speaker also served as a commentator for other lectures and facilitated Q&A sessions based on audience questions. During the lunch break, as part of the lunch program, Director Iso, a physicist, and Prof. Fumiharu Kato, a mathematician, engaged in a discussion about the future possibilities of mathematics, moderated by Ms. Shinozaki. The event was organized and hosted by Ms. Michibayashi and Mr. Katada from Academist, who helped make the event a success. The event was attended by 414 people, and at one point there were over 250 in the audience.

2025-04-23

Masazumi Honda received "Commendation for Science and Technology: the Young Scientists' Award"

Our colleague Masazumi Honda received "Commendation for Science and Technology: the Young Scientists' Award" in recognition of his outstanding research achievements in the theoretical studies of strong-coupling dynamics in quantum field theories. Congratulations to Masazumi !

2025-04-17

RIKEN Research: When it comes to modeling, even unmeasurable data tells us something

Mathematical models for predicting how cancer tumors in mice grow over time can give distorted results if unmeasurable data is ignored, a team that includes two RIKEN researchers has shown1. This finding has important implications when applying mathematical models to medicine. A self-confessed data geek, Catherine Beauchemin of the RIKEN Center for Interdisciplinary Theoretical and Mathematical Sciences (iTHEMS) specializes in applying the power of math to everything from viruses to supernovae. “I love trying to figure out what data are telling us,” she says. Seeking new insights into cancer mechanisms, Beauchemin’s team used mathematical models to analyze previously published data of tumor-size measurements over time for ten mice. To read more, please visit the related link.

2025-04-14

RIKEN Research: Refined test could improve Parkinson’s disease diagnosis

A team that includes a RIKEN researcher has refined a lab test for measuring protein aggregate levels in samples from patients with certain neurodegenerative diseases1. This has the potential to improve diagnosis and drug development for these diseases. Synucleinopathies are neurodegenerative diseases such as Parkinson’s disease and dementia with Lewy bodies. They are associated with the accumulation of aggregates of misfolded alpha-synuclein proteins in the brain and spinal cord. “When a misfolded alpha-synuclein protein in a neuron encounters one of its properly folded counterparts, it causes it to become misfolded,” says Catherine Beauchemin of the RIKEN Center for Interdisciplinary Theoretical and Mathematical Sciences. “The two misfolded alpha-synuclein proteins stick together and cause other normal alpha-synuclein to misfold and aggregate.” To read more, please visit the related link.

2025-04-14

Demonstration of Quantum Information Delocalization in a Periodically Driven System

A collaborative research team, including Visiting Scientists Yuta Kikuchi and Tomoya Hayata, has demonstrated that a scrambled state—in which quantum information becomes delocalized—can be prepared using a quantum circuit that simulates a periodically driven system. This was achieved with an ion-trap quantum computer. Scrambled states possess characteristics that are expected to be beneficial for quantum information recovery and many-body quantum system computations. This achievement represents an early-stage application of quantum computing in an academic research domain where physical phenomena and quantum information intersect, and is anticipated to contribute to the promotion of quantum computing utilization in Japan. In this study, the research team confirmed that a scrambled state—previously typically discussed using random quantum circuits—can also be prepared using periodically driven quantum circuits. This was validated through a combination of practical implementation on a high-fidelity quantum computer, appropriate error mitigation techniques, and theoretical analysis. For further details, please refer to the press release available via the related link.

2025-04-14

 A Century of Quantum Mechanics

 Interview with Mathematician Takashi Tsuboi [Part Ⅱ]

 Interview with Physicist Yasunori Nomura - Part Ⅳ

 Interview with Physicist Yasunori Nomura - Part Ⅲ

 Interview with Mathematician Takashi Tsuboi [Part Ⅰ]

 Interview with Mathematician Yuto Moriwaki [Part2]

 Interview with Mathematician Yuto Moriwaki [Part 1]

 Interview with Mathematician Eiji Inoue [Part 2] (in Japanese)

 Interview with Physicist Yasunori Nomura - Part Ⅱ

 The Connection Between Mathematics and Microbial Research: From Fisheries Science to the Path of Mathematics

 Contributed to the 'One Poster per Household' Project – Like the Ones You See in Science Classrooms

 Interview with Dr. Misako Tatsuma, a Planetary Formation Theorist

 Interview with Mathematician Eiji Inoue [Part 1]

 Interview with Physicist Yasunori Nomura - Part I

 Interview with Physicist Ryo Namba [Part 2]

 Interview with Physicist Ryo Namba [Part 1]

 Interview with Ryosuke Iritani, Mathematical Biologist [Part 1]

 Theoretical Physicist Tetsuo Hatsuda Interview Vol.2: About Research and Mathematics

 Theoretical Physicist Tetsuo Hatsuda Interview Vol.1: About RIKEN iTHEMS

 What about climate change in actuality?

 Statistical Signatures of Quantum Chaos in Non-Hermitian Systems

 Computers as a Playground for Mathematics

 The Free Will Theorem in Quantum Mechanics

 Renormalization revisited

 Renormalization: Awareness of Ignorance

 Recipe for soup of quarks and gluons

 A subjective view on what is a quantum effect

 Mathematical aspects of the entropic uncertainty relation

 Forming black holes from stars

 Singularity Theorems

 Resurgence: making sense out of non-convergent series

 How can we use a quantum computer to study the ground state of the hydrogen molecule?

 Applications and Extensions of the Nielsen-Ninomiya Theorem in Condensed Matter Physics

 COVID-19: then, now, and into the future

 Exploring Quantum Spacetime

 Classical simulations of quantum computers

 When a Cretan says all Cretans are liars

 Physical and local observables in gravitational theory

 Can you hear the shape of a drum?

 Quantum many-body physics with cold atoms

 complexity in non-unitary dynamics of photons

 Physics Through the Looking Glass

 A new B.O.A.T. in astrophysics

 Evolution and our daily rhythms

 Area law of entanglement entropy in quantum many body systems and its implication in tensor network calculation

 Comparison between conventional computers and quantum computers

 A glimpse of enumerative geometry

 Message-passing algorithms for graphical models

 Canonical form of tensor networks in one and two dimensions

 The basics of topological band theory

 Building something from nothing: a mathematical framework for aperiodic/amorphous sets

 Planetary lightning: Current State-of-the-art and outstanding questions

 Collective Power of Science ~ from the High-Energy Atmospheric Physics to our New Exploration of the Universe ~

 Morse theory and Floer theory

 Knot theory and topological semimetals

 On Dark Matter