On January 28th, iTHEMS member Don Warren co-hosted a workshop on Communication for Interdisciplinary Collaboration. The goals of this workshop were (1) to learn how to communicate with people who do not study the same topic you do, and (2) to practice explaining your work so that a non-expert can decide if they want to join your project. The workshop was open to all RIKEN staff in all fields and positions, and turnout was very good: scientists from multiple centers attended, as did several non-research staff.

Everyone who attended learned two key points to make cross-discipline communication easier and more productive. First, listen actively when someone is talking about their work to you; don’t fixate on the first interesting thing and stop listening to the rest of their explanation. Second, K.I.S.S.—keep it short and simple! (It is easy to talk about what to do, but it was much harder to practice it during the workshop.)

The workshop facilitator was Christiane Brew, a performer and trainer who uses techniques from improvisation to encourage open discussion, deep listening, and clear “pitching”. This was the second of two workshops organized in FY2019 by Don and Amanda Alvarez of CBS. Support for the workshop came from the RIKEN Collaboration Seed fund.

If this workshop is repeated next year, please consider joining and practicing your communication skills so you will be ready to start on your next interdisciplinary collaboration.

Interdisciplinary workshop "Present and Future of the Quantum Computing (QC)" hosted by MEXT and sponsored by iTHEMS and CEMS was held on Jan.29, 2020 at RIKEN Suzuki Umetaro Hall. There were more than 170 people got together from academia, industries and publishers. For the people who could not enter the hall, the talks were also broadcasted to the iTHEMS room 160. The scientific session was started with a review talk on the history of quantum-bit researches by Yasunobu Nakamura (CEMS). It was then followed by 11 talks which covered wide topics ranging from the QC architecture development to QC algorithms. The very last talk was given by our iTHEMS colleague, Jason Chang (iTHEMS/UCB), who discussed the adiabatic quantum computing and possible near-term engineering applications on the basis of his recent QC works. A poster session with about 30 posters from many different areas of science was also held with very lively discussions, especially among young researchers. Since the meeting was so successful to provide a platform for the researchers interested in this growing field of QC, we will definitely have the 2nd meeting in the near future.

As ABBL/iTHEMS seminars, Dr. Hajime SOTANI gave a talk about "Neutron stars and nuclear saturation parameters" on 24th January. So far, many equations of state (EOSs) for neutron star matter are proposed, but the EOS is not fixed yet. This is mainly because the difficulty to obtain the information for high density region via terrestrial experiments. Thus, as an inverse problem, neutron stars are a suitable laboratory for probing the nuclear properties in the high density region. In this talk, it has been discussed the possibility for constraining the nuclear saturation parameters via the neutron star observations, especially focusing on the low-mass neutron stars. Any EOSs can be expanded in the vicinity of the saturation point as a function of the baryon number density, where the expansion coefficients correspond to the saturation parameters. So, each EOS has an own set of saturation parameters. Among the saturation parameters, the incompressibility (K0) for symmetric nuclear matter and the so-called slope parameter (L) for pure neutron matter are relatively difficult to constrain, because these are a kind of the derivative around the saturation point. Thus, in particular these two saturation parameters have been focused in this talk. In addition, the EOSs for high density region can not be expressed well only with the saturation parameters, but one may be able to discuss the EOSs with the saturation parameters up to twice the saturation density. In practice, by systematically examining the masses of low-mass neutron stars constructed with various EOSs up to twice the saturation density, the suitable combination of K0 and L for expressing well the low-mass neutron stars has been found successfully, i.e., eta^3 = (K0 * L^2). That is, the neutron star mass and gravitational redshift can be expressed well as a function of eta and the stellar central density. This is suggested that the value of eta and central density could be constrained via the simultaneous observations of neutron star mass and gravitational redshift. Furthermore, using eta, the possible maximum mass of neutron stars has been discussed together with the constraint obtained from the gravitational wave event, GW170817, and NICER observation.