vol. 103 | iTHES

Vol. 103, November 24th, 2015


  • Announcement
  • Upcoming Events
  • Event report
  • Paper of the week

Paper of the week

Taku Izubuchi


Supercomputing the strange difference between matter and antimatter

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.


RIKEN Research Highlight:

"How a star turns inside out: Simulations of a supernova suggest that density variations inside a star help propel heavy elements from its core"
was released on the basis of the paper by the ithes-mcc team members and the collaborators:
J. Mao, M. Ono, S. Nagataki, M.-a. Hashimoto, H. Ito, J. Matsumoto, M. G. Dainotti, and S.-H. Lee, Astrophysical Journal 808, 164 (2015).

Upcoming Events

"A couple of recent developments in atomistic simulations of solid and soft(bio) matter"
Boero Mauro (Institut de Physique et Chimie des Materiaux de Strasbourg (IPCMS), University of Strasbourg and CNRS, UMR 7504, 23 rue du Loess, F-67034, Strasbourg, France Computational Materials Science Initiative (CMSI) at Dept. of Applied Physics, The University of Tokyo, 7-3-1 Hongo, Tokyo 113-8656, Japan)
Date:November 26th (Thu.) 10 a.m. 11月26日(木)10:00-
Place:Meeting room AB, Laser Science Laboratory 理研 和光キャンパス レーザー棟会議室AB

Abstract: A brief overview on recent advanced computational approaches used in the modeling of amorphous materials and biochemical reactions is presented, along with the most recent applications. The scope is to bring attention on advances in DFT-based techniques to extend the time and size scale of the simulations to a more realistic modeling. At the same time, we wish to underscore the still existing limitations in these methodologies. After inspecting the basic algorithms [1-2], we shall focus on their practical applications in two cases. The first one is represented by phase-change materials (PCM) [3] able to perform quick transitions between a crystal and an amorphous phase for next-generation optical supports (blue ray). The second one is a peculiar enzymatic reaction operated by a specific bacteria (arthrobacterium sp. KI72) able to “digest” synthetic fibers such as nylon-6 oligomers, resulting as byproducts in manufacturing industry [4,5].
[1] M. Boero, A. Bouzid, S. Le Roux, B. Ozdamar, C. Massobrio, Molecular Dynamics Simulations of Disordered Materials: From network glasses to phase change memory alloys, pag. 35-55, Springer, Berlin Heidelberg 2015. ISBN: 978-3-319-15674-3
[2] M. Boero and A. Oshiyama, Car-Parrinello Molecular Dynamics in Encyclopedia of Nanotechnology, pag. 1-10, Springer, Berlin Heidelberg 2015. ISBN 978-94-007-6178-0; DOI: 10.1007/978-94-007-6178-0_100946-1
[3] A. Bouzid, S. Gabardi, C. Massobrio, M. Boero, M. Bernasconi, Phys. Rev. B 91, 184201 (2015)
[4] K. Kamiya, T. Baba, M. Boero, T. Matsui, S. Negoro, Y. Shigeta, J. Phys. Chem. Lett. 5, 1210 (2014)
[5] T. Baba, M. Boero, K. Kamiya, H. Ando, S. Negoro, M. Nakano, Y. Shigeta, Phys. Chem. Chem. Phys. 17, 4492 (2015)

RIKEN Symposium
"Toward the Advanced Integrated Intelligence Research"

Date: November 28 (Sat.) 10:00-17:00
Place: Okochi hall
Y. Nakamura (CEMS), S. Nagataki (iTHES), M. Nikaido (ACCC), J. Makino (AICS), T. Miyoshi (AICS), K. Mochida (CSRS), T. Tsunoda (IMS), T. Toyoizumi (BSI), M. Taiji (QBiC), K. Takahashi (QBiC)
Language: Japanese
Contact: N. Maeda (norihiro@riken.jp)
Advanced Integrated Intelligence Research Project Preparatory Office

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.

Event report

On Nov. 20, 2015, the 7th academic-industrial lecture "Autonomous Car and Artificial Intelligence (AI)"was held at Okochi hall. The lecturer was Dr. T. Kindo from TOYOTA. More than 70 participants inside and outside of RIKEN have participated his 3-hour lecture on (i) the current status of the autonomous car technology as a typical example of the advanced AI and (ii) the basic concepts and problems of AI.
The audience were all fascinated by his stimulating and well-organized talk and by the lessons he learned from his long experiences in the AI research.
Many questions and discussions were made during and after the lecture from the people in all areas.
The lecture and the atmosphere of the Okochi hall were truly interdisciplinary.

An international workshop entitled "Nambu and Science Frontier" was held on November 17th at Osaka University. This workshop was organised as a joint activity based on the trilateral collaboration among Osaka CTSR, Kavli IPMU and iTHES. This year, the theme of the workshop was selected so that we can honour and commemorate the legacy of late Professor Yoichiro Nambu, who passed away this July. The choice of the venue was also particularly appropriate because of? Prof. Nambu's ties with Osaka University. The talks of the workshop were all related with, or have their origin with Prof. Nambu's research. Reflecting wide spreading impacts which Prof. Nambu's many seminal works, they covered from string theory to QCD, and even biology and cosmology were discussed. From iTHES, Kota Masuda, Noriaki Ogawa and Toshifumi Noumi gave a talk, while our director Tetsuo Hatsuda gave an overview of iTHES and its collaboration with Osaka U. and Kavli IPMU.

From 29. Oct. to 4. Nov. Akinori Tanaka, I, traveled to Taiwan in order to discuss with the collaborator in National Taiwan University. The photo was taken in the place called 'Jiufen' in Japanese "Kyu-hu" when I visited there in the weekend. Unfortunately, it was raining but the atmosphere was very good. This place is famous for its similarity between the stage of a Japanese anime movie 'Spirited Away' (Sen-to-chihiro-no-kamikakushi).
During my visit, there were a conference on amplitude of quantum field theory in NTU, and I could also attend the conference and enjoyed it.

Paper of the week

"Standard Model Prediction for Direct CP Violation in K-> pi pi Decay"
by Z. Bai, T. Blum, P.A. Boyle, N.H. Christ, J. Frison, N. Garron, T. Izubuchi, C. Jung, C. Kelly, C. Lehner, R.D. Mawhinney, C.T. Sachrajda, A. Soni, and D. Zhang (RBC and UKQCD Collaborations)
Phys. Rev. Lett. 115 (2015) 212001

Press Release:
"Supercomputing the strange difference between matter and antimatter"

Dr. T. Izubuchi (RIKEN BNL Center, iTHES Associate) http://www.riken.jp/en/research/labs/rnc/riken_bnl/comput/ and his team in US and England have published the first calculation of direct "CP" symmetry violation - how the behavior of subatomic particles (in this case, the decay of kaons) differs when matter is swapped out for antimatter. The direct CP symmetry violation is a tiny effect, showing up in just a few particle decays in a million. The calculation, which required more than 200 million core processing hours on supercomputers, determines the size of the symmetry violating effect as predicted by the Standard Model, and was compared with experimental results that were firmly established in 2000 at the European Center for Nuclear Research (CERN) and Fermi National Accelerator Laboratory.
Although the result from the calculation is consistent with the experimental measurement, revealing no inconsistency with the Standard Model, the calculation is on-going with an accuracy that is expected to increase two-fold within two years. That will open the possibility that evidence for new phenomena, not described by the Standard Model, may yet be uncovered.