Omega Meson from Lattice QCD

April 2 (Wed) at 15:00 - 16:00, 2025

Haobo Yan (Ph.D. Student, School of Physics, Peking University, China)

The three-body problem, renowned for its unsolvable nature in celestial mechanics and homonymous science fiction, is not only solvable in the quantum realm regarding spectra but also offers profound insights into QCD. In this talk, I will present the first-ever lattice calculation of the resonance parameters for the lightest hadron decaying into three particles, the -meson. By mapping finite-volume energy levels to infinite-volume scattering amplitude, a pole position trajectory is obtained that, when extrapolated to the physical point, shows good agreement with the experiment.

Venue: Seminar Room #359 (Main Venue) / via Zoom

Event Official Language: English

Gauge subtleties and the finiteness of loop corrections beyond slow roll

April 3 (Thu) at 14:00 - 15:30, 2025

Danilo Artigas (JSPS Postdoctoral Research Fellow, Department of Physics Ⅱ, Division of Physics and Astronomy, Graduate School of Science, Kyoto University)

Venue: Seminar Room #359

Event Official Language: English

iTHEMS Biology Study Group April Launch Meeting (Part 1)

April 3 (Thu) at 14:00 - 15:00, 2025

Let's launch our Biology Study Group activities for the new year (Part 1 of 2). This meeting will be used to (1) say welcome to new member (SPDR Kenji Okubo, and Postdoc Lucas Sort); (2) discuss Biology seminar management in light of the new iTHEMS Centre; and (3) catch up on each other's current research. Since this will probably take us 2h, this will be Part 1 of 2 (Part 2 on 4/10). On 4/3 (Part 1) we will get a 15 min introduction talk by SPDR Kenji Okubo. This meeting is open to all RIKEN and guests. You do not need to be a member of the iTHEMS Biology Study Group.

Venue: via Zoom / 4th floor public space, Main Research Building

Event Official Language: English

A Strategy for Proving the Strong Eigenstate Thermalization Hypothesis: Chaotic Systems and Holography

April 3 (Thu) at 16:00 - 17:00, 2025

Taishi Kawamoto (Ph.D. Student / JSPS Research Fellow DC, Yukawa Institute for Theoretical Physics, Kyoto University)

The strong eigenstate thermalization hypothesis (ETH) provides a sufficient condition for thermalization and equilibration. Although it is expected to hold in a wide class of highly chaotic theories, there are only a few analytic examples demonstrating the strong ETH in special cases, often through methods related to integrability. In this talk, I will explore sufficient conditions for the strong ETH that may apply to a broad range of chaotic theories. These conditions are expressed as inequalities involving the long-time averages of real-time thermal correlators. Specifically, I will discuss bottom-up holographic models that satisfy these conditions under certain assumptions, which are expected to hold in such models. This talk is based on the preprint 2411.09746 [hep-th].

Venue: Hybrid Format (3F #359 and Zoom), Seminar Room #359

Event Official Language: English

iTHEMS Biology Study Group April Launch Meeting (Part 2)

April 10 (Thu) at 16:00 - 17:00, 2025

Let's launch our Biology Study Group activities for the new year (Part 2 of 2). This meeting will be used to (1) say welcome to new member (SPDR Kenji Okubo, and Postdoc Lucas Sort); (2) discuss Biology seminar management in light of the new iTHEMS Centre; and (3) catch up on each other's current research. Since this will probably take us 2h, this will be Part 2 of 2 (Part 1 was on 4/3). On 4/10 (Part 2) we will get a 15 min introduction talk by Postdoc Lucas Sort. This meeting is open to all RIKEN and guests. You do not need to be a member of the iTHEMS Biology Study Group.

Venue: via Zoom / Hybrid Format (3F #359 and Zoom), Main Research Building

Event Official Language: English

Artificial Intelligence and Neuroscience

April 11 (Fri) at 14:00 - 15:30, 2025

Junichi Chikazoe (Professor, Center for Brain,Mind and KANSEI Sciences Research, Hiroshima University)

Recent advancements in artificial intelligence have led to various discoveries in the field of neuroscience. For example, it has been demonstrated that the information on orientation columns in the visual cortex and the basic taste information in the gustatory cortex can be extracted by applying machine learning to relatively low-resolution functional MRI data. Additionally, intriguing findings have emerged, such as the information processing structures of artificial neural circuits—designed independently of the brain—showing similarities to those of biological neural networks. In this talk, I will discuss the applications of artificial intelligence in neuroscience and explore future directions in this field.

Venue: Seminar Room #359 (Main Venue) / via Zoom

Event Official Language: English

The 28th MACS Colloquium

April 25 (Fri) at 14:45 - 18:30, 2025

Shizuo Kaji (Professor, Institute of Mathematics for Industry, Kyushu University / Professor, Center for Science Adventure and Collaborative Research Advancement (SACRA), Graduate School of Science, Kyoto University)

14:45-15:00 Teatime discussion 15:00-16:00 Talk by Prof. Shizuo Kaji (Professor, Institute of Mathematics for Industry, Kyushu University / Professor, Center for Science Adventure and Collaborative Research Advancement (SACRA), Graduate School of Science, Kyoto University) 16:15-17:20 2024 Study Group introduction session 17:30-18:30 Discussion

Venue: Science Seminar House (Map 9), Kyoto University

Event Official Language: Japanese

From Galaxies to Cosmological Structures: The Multi-Scale Influence of Cosmic Rays

June 13 (Fri) at 14:00 - 15:15, 2025

Ellis Owen (Special Postdoctoral Researcher, Astrophysical Big Bang Laboratory, RIKEN Cluster for Pioneering Research (CPR))

Cosmic rays interact with astrophysical systems over a broad range of scales. They go hand-in-hand with violent, energetic astrophysical environments, and are an active agent able to regulate the evolution and physical conditions of galactic and circum-galactic ecosystems. Depending on their energy, cosmic rays can also escape from their galactic environments of origin, and propagate into larger-scale cosmological structures. In this talk, I will discuss the impacts of cosmic rays retained in galaxies. I will show they can deposit energy and momentum to alter the initial conditions of star-formation, modify the circulation of baryons around galaxies, and have the potential to regulate long-term galaxy evolution. I will highlight some of the astrophysical consequences of contained hadronic and leptonic cosmic rays in and around galaxies, and how their influence can be probed using signatures including X-rays, gamma-rays and neutrinos. I will also discuss what happens to the cosmic rays that escape from galaxies, including their interactions with the magnetized large-scale structures of our Universe, and the fate of distant high-energy cosmic rays that do not reach us on Earth.

Venue: Hybrid Format (3F #359 and Zoom), Seminar Room #359

Event Official Language: English

Recent Developments and Challenges in Tensor Networks: Algorithms, Applications to science, and Rigorous theories

July 28 (Mon) - August 8 (Fri), 2025

Venue: Panasonic Hall, Yukawa Institute for Theoretical Physics, Kyoto University

Event Official Language: English

iTHEMS-NCTS Workshop

August 18 (Mon) - 21 (Thu), 2025

This workshop aims to strengthen collaboration between researchers at RIKEN iTHEMS and the National Center for Theoretical Sciences in Taiwan. It will be a four-day event, with the first two days dedicated to interdisciplinary topics. The last two days will focus on specialized areas, with one day devoted to condensed matter physics and the other to high-energy physics, including quantum gravity.

Venue: via Zoom / RIKEN Wako Campus

Event Official Language: English