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.

## Upcoming Events

Tomorrow

### Perspective of nuclear physics in the 21 century

September 27 at 13:30 - 17:00, 2020

Dr. Tetsuo Hatsuda
(Program Director, iTHEMS)

Prof. Hiroyoshi Sakurai
(Director, Nishina Center for Accelerator-Based Science, RIKEN)

Prof. Naohito Saito
(Director, J-PARC Center)

Prof. Takaaki Kajita
(Director, The Institute for Cosmic Ray Research (ICRR), The University of Tokyo)

世界最先端の日本の原子核物理研究を行う4施設の牽引者がそれぞれリレー方式で講義を行います。21世紀の原子核物理学の潮流といえる、重力波や中性子星連星合体など宇宙の謎に迫る高密度世界の解明に関する研究内容から、先端加速器やスーパーコンピューターを用いた最先端の研究スタイルまで、日本が誇る原子核物理学の今と今後の展望をお話します。

Venue: via YouTube Live

Event Official Language: Japanese

### Fast Radio Bursts: a cosmic mystery

September 28 at 10:30 - 11:00, 2020

Dr. Don Warren (Research Scientist, iTHEMS)

On Monday morning, iTHEMS researcher Don Warren will give a public talk on fast radio bursts. He will describe this cosmic mystery, and reveal how impatient Australians play an important role in the s...more

Venue: via Online

Event Official Language: English

### The Second Tohoku University - RIKEN Joint Workshop: "Math Meets Quantum Materials"

September 29 - 30, 2020

Prof. Hidetoshi Nishimori
(Senior Visiting Scientist, iTHEMS)

Dr. Tomoki Ozawa
(Visiting Scientist (Academia), iTHEMS)

Dr. Ching-Kai Chiu
(Senior Research Scientist, iTHEMS)

Dr. Ryusuke Hamazaki
(Senior Research Scientist, iTHEMS)

Dr. Kyosuke Adachi
(Special Postdoctoral Researcher, iTHEMS)

Dr. Christopher Bourne
(Visiting Scientist (Academia), iTHEMS)

The second Tohoku University - RIKEN joint workshop, entitled "Math Meets Quantum Materials," takes place from September 29 - 30. Tohoku University and RIKEN have been holding a series of joint wor...more

Venue: via Online

Event Official Language: English

### Public Lecture : Math meets Quantum Materials

September 29 at 19:00 - 20:30, 2020

Prof. Hidetoshi Nishimori
(Senior Visiting Scientist, iTHEMS)

Dr. Tomoki Ozawa
(Visiting Scientist (Academia), iTHEMS)

Public Lecture "Math meets Quantum Materials" for high school students and above will be held. The lecture will introduce the latest topics in mathematics and physics, such as topology and quantum com...more

Venue: via Online

Event Official Language: Japanese

### N-body simulation of DM halo

October 1 at 14:00 - 15:00, 2020

Dr. Tomoaki Ishiyama (Associate Professor, Institute of Management and Information Technologies)

Venue: via Zoom

Event Official Language: English

### TQFT, integrable lattice model, and quiver gauge theories

October 2 at 16:00 - 18:00, 2020

Mr. Toshihiro Ota (Student Trainee, iTHEMS)

- 1st part (math): In physics literature, “lattice models” appear quite often as mathematical models of physical systems, e.g. Ising model, vertex models, lattice gauge theory. The aim of the 1st part...more

Venue: via Zoom

Event Official Language: English

### Forefront of Modern Science: Frontiers in Mathematics, Astronomy, Physics, Biology and Computation

October 2 at 16:20 - 17:50, 2020

Dr. Tetsuo Hatsuda
(Program Director, iTHEMS)

Dr. Yuka Kotorii
(Visiting Scientist (Academia), iTHEMS)

Dr. Shigehiro Nagataki
(Deputy Program Director, iTHEMS)

Dr. Makiko Nio
(Senior Researcher, Nishina Center for Accelerator-Based Science, Riken)

Dr. Ryosuke Iritani
(Research Scientist, iTHEMS)

Dr. Ai Niitsu
(Postdoctoral Researcher, Theoretical Molecular Science Laboratory, RIKEN)

Dr. Shigenori Otsuka
(Research Scientist, iTHEMS)

Dr. Emi Yukawa
(Assistant Professor, Department of Physics, Faculty of Science Division I, Tokyo University of Science)

1回目 2002年10月2日 初田 哲男「数理が開く科学の扉」 2・3回目 10月9日、10月16日 小鳥居 祐香「空間の形を見る」 4・5回目 10月23日、10月30日 長瀧 重博「巨大星の爆発と中性子星・ブラックホール」 6・7回目 11月6日、11月13日 仁尾 真紀子「素粒子物理学へようこそ」 8・9回目 11月20日、11月27日 入谷 亮介「自然淘汰...more

Venue: Changed to Zoom

Event Official Language: Japanese

### Tetsuo Hatsuda x Koji Hashimoto x Aiko Teranishi "Science for the Future"-"The Usefulness of Useless Knowledge" (University of Tokyo Press) Commemorative Publication

October 10 at 15:00 - 17:00, 2020

Dr. Tetsuo Hatsuda
(Program Director, iTHEMS)

Prof. Koji Hashimoto
(Professor, Department of physics, Osaka University)

Ms. Aiko Teranishi
(President and CEO, indigo.inc)

Dr. Tetsuo Hatsuda, iTHEMS Program Director, published "The Usefulness of Useless Knowledge" in this July by the University of Tokyo Press. This book is a collection of essays by Abraham Flexner, the ...more

Venue: via Online

Event Official Language: Japanese

### MCME SYMPOSIUM 2020

October 15 - 16, 2020

Dr. Tetsuo Hatsuda
(Program Director, iTHEMS)

Dr. Ryusuke Hamazaki
(Senior Research Scientist, iTHEMS)

"MCME SYMPOSIUM 2020" will be held at the Musashino Center of Mathematical Engineering of Musashino University. This symposium is free of charge and open to everyone. [Some excerpts from the progra...more

Venue: via Online

Event Official Language: Japanese

### The Mathematical Society of Japan: Cross-discipline and cross-industry research exchange meeting 2020

October 31 at 10:00 - 17:00, 2020

「数学・数理科学専攻若手研究者のための異分野・異業種研究交流会（研究交流会）」は、 数学・数理科学専攻の博士課程学生をはじめとする若手研究者と産業界を含む異分野の方々 との「双方向の交流の場」として2014年から開催しております。若手研究者の皆様に、諸科学や産業への応用展開のような数学の思わぬ力を発見してもらう ことや、産業界を含む様々な分野で活躍できる場の存在を認識してもらうことが主たる目的 で...more

Venue: via Online

Event Official Language: Japanese

## Opportunities

### Seeking a Postdoctoral Researcher (W20086) *theoretical physics

Deadline: Open until filled

iTHEMS is seeking a postdoctoral researcher in theoretical physics including condensed matter physics, particle physics and nuclear physics. In particular, the successful applicant is expected to help develop an adiabatic quantum computer (AQC) simulator using time-dependent density matrix renormalization group (DMRG). This project is part of a greater effort in the Berkeley area towards exploring the efficacy of adiabatic quantum computing supported jointly by RIKEN, UC Berkeley, Lawrence Berkeley Lab, and the U.S. Department of Energy. In addition to developing the AQC simulator, the candidate will have the opportunity to pursue top-level research in collaboration with an interdisciplinary group of researchers across fields such as mathematics, physics, chemistry, life sciences, engineering computational sciences, information sciences, and social sciences at iTHEMS, and physics, mathematics and computational sciences at Berkeley.

### Seeking a Postdoctoral Researcher or Research Scientist (W20001) *condensed matter theory

Deadline: October 31, 2020

iTHEMS is seeking postdoctoral researcher(s)/research scientist(s) in theoretical condensed matter physics. Successful applicant(s) are expected not only to pursue top-level researches in their own field but also to lead interdisciplinary collaborations among different fields such as mathematics, physics, chemistry, life sciences, engineering, computational sciences, information sciences, and social sciences, under the concept of iTHEMS. This time, we encourage junior applicants who have high research potential in theoretical studies of topological states of matter, Majorana modes, topological quantum computing, mathematical physics, non-Hermitian systems, and related fields.

### Seeking a Postdoctoral Researcher or Research Scientist (W20002) *machine learning

Deadline: October 31, 2020

iTHEMS is seeking postdoctoral researcher(s)/research scientist(s) in the field of machine learning. Successful applicant(s) are expected not only to pursue top-level researches in their own field but also to lead interdisciplinary collaborations among different fields such as mathematics, physics, chemistry, life sciences, engineering, computational sciences, information sciences, and social sciences, under the concept of iTHEMS. This time, we encourage junior applicants who have high research potential in theories and applications of machine learning.

### Seeking a Postdoctoral Researcher or Research Scientist (W20014) *particle physics and quantum gravity

Deadline: October 31, 2020

iTHEMS is seeking postdoctoral researcher(s)/research scientist(s) in the field of particle physics and quantum gravity. Successful applicant(s) are expected not only to pursue top-level researches in their own field but also to lead interdisciplinary collaborations among different fields such as mathematics, physics, chemistry, life sciences, engineering, computational sciences, information sciences, and social sciences, under the concept of iTHEMS. In particular, we welcome applications from young researchers who are interested in exploring the properties of spacetime and matter under extreme conditions such as black holes and the early universe, as well as the theory of quantum gravity in a broader sense.

### Seeking a Postdoctoral Researcher (W20090) *mathematical sciences

Deadline: December 14, 2020

iTHEMS is seeking postdoctoral researcher(s) in the field of mathematical sciences (including pure mathematics and applied mathematics). Successful applicant(s) are expected not only to pursue top-level researches in their own field but also to promote interdisciplinary collaborations among different fields such as mathematics, physics, chemistry, life sciences, engineering, computational sciences, information sciences, and social sciences, under the concept of iTHEMS. This time, we encourage junior applicants who have high research potential in the field of mathematical sciences, who can actively communicate with researchers in iTHEMS. iTHEMS has a senior research scientist, Dr. Hiroyasu Miyazaki (arithmetic/algebraic geometry), and researchers from various field of mathematical sciences, including analysis, partial differential equations, topology, gauge theory, mathematical physics, etc.

## Latest News

2020-09-25

### Self-introduction: Catherine Beauchemin

Bonjour! I was already a member of iTHEMS as a Senior Visiting Scientist so probably you already know me. But since September 2020, I became a Deputy Program Director of iTHEMS. I was looking forward ...more

2020-09-25

### Biology Seminar by Dr. Kyosuke Adachi on September 23, 2020

On September 23rd, Kyosuke Adachi gave a talk at the iTHEMS Biology Seminar on phase transitions in Biology. He first introduced the concept of phase transition and its possible application to underst...more

2020-09-24

### Week 4 of September

Title: Polynomial growth of out-of-time-order correlator in arbitrary realistic long-range interacting systems Author: Tomotaka Kuwahara, Keiji Saito arXiv: http://arxiv.org/abs/2009.10124v1 Titl...more