vol. 100 | iTHES

Vol. 100, November 2nd, 2015


  • Announcement
  • Upcoming Events
  • Paper of the week

Paper of the week


Deformed Prepotential, Quantum Integrable System and Liouville Field Theory

From the Office

The office of iTHES assistant, Ms.Chikako Oota is situated at the second floor of the main research building, room # 246. The extension number is 3261. She will be at the office from 10 a.m. to 16 p.m.


We are proud to present this commemorative 100th issue of iTHES Newsletter. The messages from some of the ithes members for the occasion follow.

Tetsuo Hatsuda (ithes director and ithes-phys team leader):
It is our great pleasure to deliver the 100th issue of the iTHES Newsletter today.First of all, I would like to thank Dr. Tsukasa Tada and Ms. Chikako Oota to make this big milestone possible. Without their tremendous efforts of "every" week,this memorable occasion could not come. As reported in the recent Nature article
(in which iTHES is featured together with other interdisciplinary activities in the world), interdisciplinarity is surely important for the future of science but it is also difficult to be realized in daily scientific works. For the past 2.5 years, iTHES has been organized various activities (iTHES colloquiums, iTHES seminars, iTHES coffee meetings etc) to enhance the interactions among scientists to cross the borders. Among others, the "weeky" iTHES Newsletter has been played particularly important roles. A Japanese proverb says "継続は力なり" (Persistence pays off). I hope that we can celebrate 200th iTHES Newsletter in 2.5 years.

Franco Nori (ithes-cond team leader):
In the book "The Art of Scientific Investigation", Cambridge University professor William Beveridge wrote that successful scientists “have often been people with wide interests,” which led to their originality: Originality often consists in linking up ideas whose connection was not previously suspected." He also suggested that "scientists should expand their knowledge outside of their own field, in order to add to their knowledge" (so they would have more dots which could be connected later on). A great aspect of iTHES is that it facilitates connections among different fields, driving creative ideas. This is crucially important, to counter the widespread super-narrow specialization which is restricting innovation.

Atsushi Mochizuki (ithes-bio team leader):
Congratulation for the achievement! The newsletters have provided us not only the scientific topics but also the seeds of communications among us. I express deep thanks to the great efforts by Tada-san and Hatsuda-san, and other responsible people. I will enjoy the newsletter continuously on.



Shigenori Nagataki (ithes-mcc team leader):
We know it is not easy to do something continuously for a long time. So, it is really great to hear that we will publish the 100th iTHES Newsletter. This proves that the concept of iTHES is fine and fruitful. I would like to thank Hatsuda-sama and all of the members of iTHES for their continuous interest in & efforts for the interdisciplinary theoretical science.


Tsukasa Tada (ithes colloquium committee chair):
As we celebrate the hundredth newsletter, on behalf of the iTHES colloquium committee which arranges iTHES-wide academic gatherings such as iTHES colloquia and Academic-Industrial lectures, I would like to thank our fellow members of iTHES for your cooperations and participations. Please keep joining these activities since they consist one of the linchpins of the iTHES organization. We would appreciate your inputs to make these activities more beneficial.


Koji Hashimoto (ithes founding member):
Dear members of iTHES, I am very happy that iTHES continuously grows and reaches 100th newsletter, congratulations! My Osaka University is in cooperation with iTHES, let us enhance communications more, through exchanges of researchers and ideas. I look forward to collaborations.


Gordon Baym (ithes senior visiting scientist):
My heartiest congratulations to iTHES, which has become a premier institution for interdisciplinary research -- in Japan and on the international stage. Visiting RIKEN and iTHES as a senior scientist always gives me the deep pleasure of seeing theoreticians from all fields of physics interacting so well together, and making iTHES so much more than the sum of its parts.

iTHES featured in RIKEN Research
An article overviewing the aim and the activities of iTHES was written by iTHES director, Tetsuo Hatsuda. It will be published as a part of RIKEN Research and is now on-line at
We hope it helps you to grasp the wide range of iTHES activities.

Upcoming Events

13th iTHES Colloquium

November 10th (Tue.) 15:00-
"Complex Systems Modeling and its Applications"
Prof. Kazuyuki Aihara (The University of Tokyo)
Place: 2F Large mtg.rm, Main Cafeteria (Bldg. C61)
In this talk, I review our recent reseach on complex systems modeling and its transdisciplinary applications. First, I explain about a platform for mathematical modeling of complex systems, based on complex systems control theory, complex network theory, and big data analysis. Second, I illustrate examples of its transdisciplinary applications such as dynamical network biomarkers for preemptive medicine, transitive dynamics of the primate prefrontal cortex, and an electronic AD converter with beta expansion.

"The helium Efimov trimer and larger bosonic droplets"
Prof. Doerte Blume (Washington State University)
Date: Nov. 12th (Thursday) 2015 (14:00-)
Place: Main research building, 2th floor, 224
Language: English

The quantum mechanical three-body problem has been studied extensively for about a century. The helium atom (two electrons and a nuclues) and the molecular hydrogen ion (two protons and one electron) are textbook examples that illustrate the organization of the periodic table and molecular binding mechanisms, respectively. In 1970 Vitaly Efimov predicted a rather different and counterintuive quantum mechanical three-body binding mechanism that leads to an infinite series of stable three-body states of enormous spatial extents. These Efimov states are predicted to exist for short-range interactions like the van der Waals force between atoms or the strong force between nucleons. When the potential becomes so shallow that the last two-body bound state is at the verge of becoming unbound or is unbound, then three particles stick together to form Efimov states. This talk will review recent theoretical and experimental advances in this field. The observation of the helium trimer (three neutral helium atoms) Efimov state and extensions of the Efimov scenario to four- and higher-body systems will be discussed.

Detailed information can also be found in

Osaka CTSR - Kavli IPMU - RIKEN iTHES International workshop
"Nambu and science frontier"

Date: 17th November (Tue), 2015
Venue: H701 lecture room, Dept. of Physics, Osaka university
Time: 9:30 - 17:30

Invited speakers
Kenji Fukushima (U. Tokyo)
Koji Hashimoto (Osaka U)
Simeon Hellerman (Kavli IPMU)
Noriyoshi Ishii (Osaka U)
Kota Masuda (RIKEN iTHES)
Yu Nakayama (Kavli IPMU / Caltech)
Toshifumi Noumi (Hong Kong U. of Science and Technology / RIKEN iTHES)
Kin-ya Oda (Osaka U)
Noriaki Ogawa (RIKEN iTHES)
Haruki Watanabe (MIT)
Tamiaki Yoneya (U. Tokyo, Open Univ. of Japan)

Koji Hashimoto, Kentaro Nagamine (Osaka CTSR)
Tetsuo Hatsuda, Tsukasa Tada, Masato Taki (RIKEN iTHES)
Hitoshi Murayama (Kavli IPMU)

Purpose of the Workshop:
In July 2015, we as the physics community were greatly saddened by the news that Prof. Yoichiro Nambu had passed away. He proposed many of the fundamental concepts that underlie our current understanding in theoretical sciences. On this occasion, we’d like to discuss the relevance of Nambu’s concepts and how they will be developed in many areas of science, and promote interdisciplinary collaborations among theoretical sciences. The joint workshop of Osaka CTSR- RIKEN iTHES - Kavli IPMU is a successive series following the symposium held at Kavli IPMU last year.
The topic of the workshop includes:
- Nambu-Goto action for strings, membranes and higher dim. objects
- Nambu-Goldstone theorem and its extensions
- Nambu-Jona-Lasinio model and its generalizations
- Nambu-Bethe-Salpeter equation and nuclear/hadron physics
- Nambu bracket for quantizing membrane and M-theory
- Higgs inflation
- QCD chiral phase transition
- Symmetry breaking in physical biology

Sponsored by
- Core for Theoretical Science Research (CTSR) , Osaka Univ.
- Interdisciplinary Theoretical Science (iTHES) Research Group, RIKEN
- Kavli IPMU, The Univ. of Tokyo

The 7th iTHES Academic-Industrial Innovation Lecture

"Autonomous Car and Artificial Intelligence"
Dr. Toshiki Kindo (TOYOTA)
Date: Nov. 20(Fri.) 13:30-16:00
Place: Okochi Hall, Wako, RIKEN
(Lecture is given in Japanese.)

#16 Pioneer project seminar

"Precision Tests of Discrete symmetries at Low Energies"
Prof. Klaus Jungmann (University of Groningen)
Date: Nov. 24th (Tuesday) 2015 (10:00-11:00)
Place: Main research building, 5th floor, 535,537
Language: English

Fundamental Physics Using Atoms 2015
- Towards better understanding of our matter universe -

Nov. 30 (Mon.) -- Dec. 1 (Tue.), 2015
Oral sessions: RIKEN Wako, Okochi Hall (C32)
Poster sessions: Welfare and Conference Bldg. 2F (C61)

Recently much effort has been directed to investigation of the fundamental physics which exploits remarkable developments in atomic physics and/or quantum optics techniques. Examples include (A) test of the time reversal invariance by observing permanent electric dipole moments of atoms or molecules, (B) neutrino mass spectroscopy using atoms, (C) measurement of fine structure constant's time dependence with precession atomic clock etc. This conference aims to bring together recent research results, to discuss future prospects, and to expand research network, making this field more active and productive.

Paper of the week

Last month a paper of mine I wrote with my friend Kazunobu Maruyoshi was awarded Particle Physics Medal: Young Scientist Award in Theoretical Particle Physics,, so let me explain a little about this paper. This paper “Deformed Prepotential, Quantum Integrable System and Liouville Field Theory” discussed an intersection of three different topics in theoretical physics: gauge theories, 2d critical phenomena and quantum integrable systems. Background of our work is as follows. In 2009, a surprising connection between 4d N=2 SUSY gauge theories and 2d critical phenomena was found by F.Alday, D.Gaiotto and Y.Tachikawa, and this connection is now called the AGT correspondence. This conjectural relation implies that the partition functions of 4d SUSY gauge theory of certain class is given exactly by a correlation function of a corresponding critical phenomena in 2d (conformal field theory, CFT). This mysterious AGT relation led to massive applicational results on N=2 gauge theory.

In this context, we pointed out concretely that the relation suggests another connection between 4d theories and new stuff integrable system. Actually, we showed that the partition function of gauge theory behaves as the wave function of certain 1d quantum mechanics. The Hamiltonian of this 1d system appears as a constraint equation of corresponding correlation function in 2d CFT side. Moreover, this 1d system has a solvable structure integrable system and in a sense, such integrable nature “masterminds” the mysterious AGT correspondence. Now that we string theorists pick up mathematical structure behind particle physics and utilize it on a daily basis, I’d like to apply our skill to various problems in theoretical science.