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Workshop In Session
Condensed Matter Physics of QCD 2024
March 11 (Mon) - 22 (Fri), 2024
Gordon Baym (Professor Emeritus, University of Illinois, USA)
Muneto Nitta (Professor, Keio University)
Mark Alford (Professor, Washington University in St. Louis, USA)
Sanjay Reddy (Professor, University of Washington, USA)
Dam Thanh Son (Professor, The University of Chicago, USA)
Mikhail Stephanov (Professor, The University of Illinois at Chicago (UIC), USA)
Kenji Fukushima (Professor, Department of Physics, Graduate School of Science, The University of Tokyo)
Naoki Yamamoto (Associate Professor, Keio University)
Koutarou Kyutoku (Associate Professor, Graduate School of Science, Kyoto University)
Yui Hayashi (Postdoctoral researcher, Yukawa Institute for Theoretical Physics, Kyoto University)
Kentaro Nishimura (Postdoctoral researcher, Hiroshima University)
Toru Kojo (Associate professor, Tohoku University)
Masakiyo Kitazawa (Lecturer, Yukawa Institute for Theoretical Physics, Kyoto University)QCD at finite temperature and density is one of the most challenging problems in modern physics, which plays a crucial role to understand the origin and coevolution of the universe and matter. On the one hand, the relativistic heavy-ion collision experiments in the past decades have opened a new and exciting field to explore physical properties of such a QCD matter at high-tempearture. On the other hand, recent astrophysical observations of compact stars (in particular, events involving neutron stars) is becoming another exciting tool to unveil properties of the dense QCD matter. This molecule-type workshop is aimed at bringing together theorists working on QCD at finite-temperature and density, with a particular focus on dense quark-nuclear matter relevant to neutron star physics. We will mainly cover macroscopic properties of the finite-density QCD matter such as the Lee-Yang edge singularity for a QCD critical point, the renewed Fermi liquid theory for quark-nuclear matter, nuclear superfluidity, color superconductivity, quark-hadron continuity, quantum vortex, and transport phenomena including the weak-intearction processes.
Venue: via Zoom / Yukawa Institute for Theoretical Physics, Kyoto University
Event Official Language: English
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Seminar
Multimessenger probes of superheavy dark matter decay and annihilation
March 26 (Tue) at 10:18 - 11:00, 2024
Saikat Das (Postdoctoral Fellows, Yukawa Institute for Theoretical Physics, Kyoto University)
We revisit constraints on decaying very heavy dark matter (VHDM) using the latest ultrahigh-energy cosmic-ray (UHECR; E >1e18 eV) data and ultrahigh-energy (UHE) gamma-ray flux upper limits, measured by the Pierre Auger Observatory. We present updated limits on the VHDM lifetime for masses up to ∼ 1e15 GeV, considering decay into quarks, leptons, and massive bosons. In particular, we consider not only the UHECR spectrum but their composition data that favors heavier nuclei. Such a combined analysis improves the limits at <1e12 GeV because VHDM decay does not produce UHECR nuclei. We also show that the constraints from the UHE gamma-ray upper limits are ∼ 10 times more stringent than that obtained from cosmic rays, for all of the Standard Model final states we consider. The latter improves our limits to VHDM lifetime by a factor of two for dark matter mass >1e12 GeV. We also provide constraints using neutrino flux from dark matter decay, including the neutrino-induced cascades. We consider the interaction of UHE neutrinos with the cosmic neutrino background, leading to the attenuation of the extragalactic flux reaching Earth, which improves our analysis to obtain tighter constraints.
Venue: via Zoom
Event Official Language: English
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Seminar
Arrhythmic activity rhythms in ants
March 26 (Tue) at 16:00 - 17:00, 2024
Haruna Fujioka (Assistant Professor, Faculty of Environmental, Life, Natural Science and Technology, Okayama University)
Most organisms exhibit a periodic activity of about 24 h. This circadian rhythm is considered to be an adaptation to the fluctuations of the environment. In social insects such as honeybees and ants, individual behavior, including activity-rest rhythms, is influenced by interactions within the colony. However, it is challenging to monitor individual activity-rest rhythms in an ant colony due to their large group size and small body size. To address this, we developed an image-based tracking system using 2D barcodes a monomorphic ant and measured the locomotor activities of all colony members under laboratory conditions. Activity-rest rhythms appeared only in isolated ants, not under colony conditions. This suggests that a mixture of social interactions, not light and temperature, induces the loss of activity-rest rhythms. These findings contribute to our understanding of the diverse patterns of circadian activity rhythms in social insects.
Venue: via Zoom
Event Official Language: English
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Special Lecture
Kyoto University SACRA-RIKEN iTHEMS Special Lecture by Prof. Tadashi Tokieda
March 28 (Thu) at 13:30 - 16:30, 2024
Tadashi Tokieda (Professor, Department of Mathematics, Stanford University, USA)
This event will be conducted in Japanese.
Venue: Large Conference Room, The Kyoto University Tokyo Office
Event Official Language: Japanese
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Special Lecture
TadaFest 2024: Toward understanding of the Origin of Spacetime
April 2 (Tue) at 14:00 - 18:00, 2024
Tsukasa Tada (Coordinator, iTHEMS / Vice Chief Scientist, iTHEMS)
Program 14:00-14:05 Welcome address T. Hatsuda (RIKEN iTHEMS) 14:05-15:35 T. Tada (RIKEN iTHEMS) "Toward understanding of the origin of spacetime" (This talk is in English) 15:35-16:00 coffee break 16:00-16:30 Shin Nakamura (Chuo Univ.) title: TBA (This talk is in Japanese) 16:30-17:00 Kinya Oda (Tokyo Woman's Chiristian Univ.) title: TBA (This talk is in Japanese) 17:00-17:30 Gen Tatara (RIKEN, CEMS) title: TBA (This talk is in Japanese) 17:30-18:00 Asato Tsuchiya (Shizuoka Univ.) title: TBA (This talk is in Japanese) 18:15- informal discussion @ Common space on 3F of the main research building
Venue: Okochi Hall (Main Venue) / via Zoom
Event Official Language: English
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Colloquium
The 25th MACS Colloquium
April 19 (Fri) at 14:45 - 18:30, 2024
Wataru Morita (Researcher, Department of Anthropology, National Museum of Nature and Science / Associate Professor, Department of Biological Sciences, Graduate School of Science, The University of Tokyo)
14:45-15:00 Teatime discussion 15:00-16:00 Talk by Dr. Wataru Morita (Researcher, Department of Anthropology, National Museum of Nature and Science / Associate Professor, Department of Biological Sciences, Graduate School of Science, The University of Tokyo) 16:15-17:20 2024 Study Group introduction session 17:30-18:30 Discussion
Venue: Maskawa Hall, 1F, Maskawa Building for Education and Research
Event Official Language: Japanese
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Workshop
Recent Developments and Challenges in Topological Phases
June 3 (Mon) - 14 (Fri), 2024
Thanks to intensive research efforts, topology has been established as a fundamental concept in physics. For closed quantum systems, the classification of gapped topological phases has matured. Moreover, the importance of topology is not limited to isolated quantum systems. Recently, the topology of non-Hermitian Hamiltonians, which effectively describe systems with dissipation, has attracted much attention worldwide. This fascination is exemplified by topological phases and topological phenomena unique to non-Hermitian systems. Against this background, the primary purpose of this workshop is to bring together researchers working on topological phases and to discuss (i) open questions in topological phases of closed quantum systems and (ii) the role of topology in open quantum systems and measurements.
Venue: Yukawa Institute for Theoretical Physics, Kyoto University
Event Official Language: English