96 events in 2019

Seminar
The 32nd QCD Club
December 26 (Thu) at 15:00  17:00, 2019
Event Official Language: Japanese

RIKENKyushu workshop on particle, nuclear and astrophysics
December 23 (Mon)  24 (Tue), 2019
Organizers Emiko Hiyama (Kyushu U./RIKEN) Hiroshi Suzuki (Kyushu U.) Tetsuo Hatsuda (RIKEN)
Venue: Faculty of Science, Ito Campus, Kyushu University
Event Official Language: Japanese

2019 RIKEN Symposium: Understand to Predict the properties of Things and Matters through Computational Calculations ~ Data Science, Natural Intelligence and Category Theory~
December 23 (Mon) at 9:50  18:10, 2019
This workshop is supported by RIKEN iTHEMS (RIKEN Interdisciplinary Theoretical and Mathematical Sciences Program).
Venue: Okochi Hall
Event Official Language: Japanese

Seminar
Constraining superheavy dark matter with the multimessenger observations of accompanying radiation
December 20 (Fri) at 14:00  15:00, 2019
Yana Zhezher (Institute for Cosmic Ray Research (ICRR), The University of Tokyo)
One of the main alternatives for the weakly interacting massive particles (WIMP) dark matter scenario are the superheavy X particles with masses larger than the weak scale by orders of magnitude. We assume the experimentally more plausible scenario of decaying superheavy dark matter (SHDM), which leads to the production secondary particles: electrons, positrons, gamma rays and neutrinos. The hypothetical Xparticle has two main parameters: it’s mass MX and lifetime ?, which can be indirectly constrained by comparisons of predicted flux of secondary particles with the astrophysical observations. We present the limits on the SHDM parameters derived with the multimessenger data from the FermiLAT, IceCube and other experiments.
Venue: Seminar Room #132
Event Official Language: English

Scalable Majorana vortex modes in ironbased superconductors
December 18 (Wed) at 13:30  15:00, 2019
ChingKai Chiu (Senior Research Associate, Kavli Institute for Theoretical Sciences, University of Chinese Academy of Sciences, China)
The ironbased superconductor FeTexSe1−x is one of the material candidates hosting Majorana vortex modes residing in the vortex cores. It has been observed by recent scanning tunneling spectroscopy measurement that the fraction of vortex cores possessing zerobias peaks decreases with increasing magnetic field on the surface of FeTexSe1−x. The hybridization of two Majorana vortex modes cannot simply explain this phenomenon. We construct a threedimensional tightbinding model simulating the physics of over a hundred Majorana vortex modes in FeTexSe1−x. Our simulation shows that the Majorana hybridization and disordered vortex distribution can explain the decreasing fraction of the zerobias peaks observed in the experiment; the statistics of the energy peaks off zero energy in our Majorana simulation are in agreement with the experiment.
Venue: #435437, Main Research Building
Event Official Language: English

Multiple Zeta Values: Interrelation of Series and Integrals
December 17 (Tue) at 16:00  18:10, 2019
Syuji Yamamoto (Associate Professor, Keio University)
Plan of the seminar: we separate each talk into two. In the first 60 minutes the speaker gives an introductory talk for nonmathematicians. After a short break, the second 60 minutes is spent for a bit more detailed talk for mathematicians (working in other areas). We welcome you joining both parts of the seminar or only the first/second half. Abstract: This is an introduction to multiple zeta values (MZVs). Although the study of MZVs is related to various areas of mathematics, we will concentrate on the algebraic structures of MZVs themselves. The key point is that MZVs have two kinds of representations: nested series and iterated integrals. We present how these two representations yield rich algebraic relations among MZVs.
Venue: Seminar Room #160
Event Official Language: English

Seminar
Weak lensing cosmology by Subaru HSC survey
December 12 (Thu) at 10:30  12:00, 2019
Chiaki Hikage (Project Associate Professor, Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU), The University of Tokyo)
Place: IPMU seminar room C
Venue: Kavli IPMU Building
Event Official Language: English

Seminar talk on GRB190114C
December 11 (Wed) at 13:45  15:30, 2019
Susumu Inoue (Research Scientist, iTHEMS)
Detection of very high energy gammarays (~TeV) from GRB190114C by MAGIC telescope is reported in the latest nature issue. Dr. Susumu Inoue (iThems) who is one of MAGIC team members will give a seminar talk on this exciting event.
Venue: Seminar Room #132
Event Official Language: English

Young Researcher Association for Biological Rhythms 2019
December 7 (Sat)  8 (Sun), 2019
Lecturers: Hiroshi Ito (Kyushu University) Shigehiro Ohdo (Kyushu University) Hiroyuki Kubota (Kyushu University) Gen Kurosawa (RIKEN) Shin G. Goto (Osaka City University) Fustin JeanMichel (Kyoto University) Organizers: Minako Isoda (Kyoto University) Kyohei Uemoto (Kyoto University / Nara Institute of Science and Technology) Shingo Gibo (RIKEN) Motohide Seki (Kyushu University) Yusuke Nakane (Nagoya University) Arisa Hirano (University of Tsukuba) This workshop is supported by RIKEN iTHEMS (RIKEN Interdisciplinary Theoretical and Mathematical Sciences Program).
Venue: School of Agriculture, Ito Campus, Kyushu Univiesiry
Event Official Language: Japanese

Seminar
Noncommutative crepant resolutions and some higher dimensional flops
December 4 (Wed) at 16:00  18:10, 2019
Wahei Hara (JSPS Research Fellow, School of Science and Engineering, Waseda University)
Plan of the seminar: we separate each talk into two. In the first 60 minutes the speaker gives an introductory talk for nonmathematicians. After a short break, the second 60 minutes is spent for a bit more detailed talk for mathematicians (working in other areas). We welcome you joining both parts of the seminar or only the first/second half. Abstract: We will talk about the theory noncommutative resolution of singularities. Noncommutative resolution is a noncommutative analog of usual (geometric) resolution of singularities, and allows us to generalise the idea of McKay correspondence to a large class of singularities. In the first part of the talk, we discuss the classical McKay correspondence, the definition of noncommutative crepant resolution, and some known results in lower dimensions. In the second half, we will discuss some concrete examples of noncommutative crepant resolutions in higher dimensions.
Venue: Seminar Room #160
Event Official Language: English

Workshop
Workshop on Virtual Reality［Session 2］
November 26 (Tue) at 10:00  18:00, 2019
Gilles Ferrand and Don Warren will run a workshop on using virtual reality (VR) for data visualization and research. Anyone from any RIKEN campus, and any field of study, is welcome. We want to build a crossdisciplinary group of people with a shared interest in VR, and to apply this tool to a broad range of data types and topics. Please check the workshop website for uptodate information ! Workshop on Virtual Reality［Seeeion 1］was held on Oct.7, 2019.
Venue: Seminar Room #132
Event Official Language: English

Seminar
A multiscale study of turbulent heating in hot accretion flows
November 18 (Mon) at 14:00  15:00, 2019
Yohei Kawazura (Assistant Professor, Tohoku University)
Recently, the Event Horizon Telescope (ETH) collaboration revealed the stunning picture of radiation from the vicinity of the black hole. For accurate interpretation of the observation, it is crucial to understand the nature of plasma in the accretion disk. The disks that EHT is observing are called radiatively inefficient accretion flows, in which the plasma is hot and dilute, and consequently collisionless. In collisionless plasma, ions and electrons can have different temperatures as they do not thermally relax through Coulomb interaction. The iontoelectron temperature ratio is the key to interpreting the observation because we can measure only the electrons' energy via radiation. To study ion and electron heating, kinetic treatment, rather than hydrodynamic treatment, is necessary. However, kinetic plasma turbulence is an extremely challenging subject. Therefore, we utilized gyrokinetics that is widely used in magnetic confinement fusion research. Our new multiscale approach treats a "large scale" where turbulence is driven by magnetorotational instability via MHD, and a "small scale" where turbulence is dissipated via gyrokinetics. Using this approach, we formulated a prescription of iontoelectron heating ratio. In my talk, I will also present basic knowledge that is necessary to study collisionless turbulent heating.
Venue: Seminar Room #132
Event Official Language: English

The 10th MACS Colloquium
November 15 (Fri) at 14:45  18:45, 2019
Nami Sakai (Chief Scientist, Star and Planet Formation Laboratory, RIKEN Cluster for Pioneering Research (CPR))
Kazuya Watanabe (Professor, Graduate School of Science, Kyoto University)14:45 Teatime 15:00 Talk by Dr. Nami Sakai 16:15 Talk by Prof. Kazuya Watanabe 17:45 Discussion The 10th MACS colloquium supported by iTHEMS. It will be broadcasted to Wako, but if you can join the colloquium physically in Kyoto, that would be better. iTHEMS provides good confectionery at Kyoto!
Venue: Lecture room #401, Graduate School of Science Building No 6, Kyoto University
Event Official Language: Japanese

Variational methods in quantum annealing
November 15 (Fri) at 13:30  15:00, 2019
Shunji Matsuura (Fundamental Researcher, Quantum Simulation Division, 1QBit, Canada)
The rapid progress in the manufacturing of quantum computing hardware has opened up the possibility of exploring its application in solving computationally challenging problems. In this work, we present variational methods in quantum annealing for solving problems more efficiently than the standard adiabatic methods. Important limitations common to all nearterm quantum devices include the absence of error correction and the short coherence time, which restrict the computational power of these systems. Therefore, shortening the time taken to perform an individual run of a quantum algorithm and making the annealing process noise resilient is essential for successfully obtaining accurate results. The efficiency of the methods is demonstrated in the groundstate energy estimation of simple molecular systems. Compared with the standard annealing method, the variational algorithms show significant improvements in the annealing time required to achieve a high accuracy.
Venue: #433, Main Research Building
Event Official Language: English

RIKEN Open Campus in Kobe
November 9 (Sat) at 10:00  16:30, 2019
Takumi Doi (Senior Research Scientist, iTHEMS / Senior Research Scientist, Quantum Hadron Physics Laboratory, RIKEN Nishina Center for AcceleratorBased Science (RNC))
RIKEN Open Campus in Kobe will be held on Nov.9, 2019. Dr. Emiko Hiyama (Kyushu Univ.) and Dr. Takumi Doi (Nishina Center / iTHEMS) will give lectures on computational nuclear and particle physics at Kobe IIB building where SUURICOOL Kobe is located. Please inform the news to anybody who are interested in visiting RIKEN Kobe.
Venue: Integrated Innovation Building (IIB)
Event Official Language: Japanese

Seminar
Some topics in projective geometry of algebraic varieties
November 8 (Fri) at 16:00  18:10, 2019
Atsushi Ito (Assistant Professor, Graduate School of Mathematics, Nagoya University)
Plan of the seminar: we separate each talk into two. In the first 60 minutes the speaker gives an introductory talk for nonmathematicians. After a short break, the second 60 minutes is spent for a bit more detailed talk for mathematicians (working in other areas). We welcome you joining both parts of the seminar or only the first/second half. Abstract: We talk about Gauss maps and projective dual varieties, which are classical objects in projective geometry of algebraic varieties. In particular, we explain Gauss maps in positive characteristic and projective dual varieties of toric varieties in characteristic 0.
Venue: Seminar Room #160
Event Official Language: English

Workshop
Collaborative Meeting on Supernova Remnants between Japan and USA
November 7 (Thu)  12 (Tue), 2019
The aim of the workshop is to bring together experts on supernova remnants and related topics for active discussions and to initiate possible collaborations among the participants. The workshop will be held at RIKEN Wako campus (first week, Nov. 7th and 8th) and Kyoto University (second week, Nov. 11th and 12th). This workshop is supported by iTHEMS (RIKEN Interdisciplinary Theoretical and Mathematical Sciences Program) and rEMU (RIKEN Pioneering Project:Evolution of Matter in the Universe).
Venue: Okochi Hall / 224226, Main Research Building / SUURICOOL (Kyoto)
Event Official Language: English

Semiclassical defect measures and observability estimate for Schrödinger operators with homogeneous potentials of order zero
October 30 (Wed) at 8:40  10:00, 2019
Keita Mikami (Research Scientist, iTHEMS)
Seminar will be held from 15:40 to 17:00 on Oct.29(PDT, the U.S. Pacific Daylight Time) as a Harmonic Analysis and Differential Equations Seminar.
Venue: UC Berkeley
Event Official Language: English

Seminar
AtiyahHirzebruch spectral sequence in the band theory
October 24 (Thu) at 16:00  18:10, 2019
Ken Shiozaki (Assistant Professor, Yukawa Institute for Theoretical Physics, Kyoto University)
Plan of the seminar: we separate each talk into two. In the first 60 minutes the speaker gives an introductory talk for nonmathematicians. After a short break, the second 60 minutes is spent for a bit more detailed talk for mathematicians (working in other areas). We welcome you joining both parts of the seminar or only the first/second half. Abstract: The topological nature of the band theory in crystalline systems can be well described by the topological Ktheory over the Brillouin zone torus. In the first part of my talk, I will present the bandtheory understanding of the grading of the Kgroup, and how the exactness axiom and the MayerVietoris sequence are naturally understood. In the second part, I discuss how to compute the differentials of the AtiyahHirzebruch spectral sequence associated with a cell decomposition.
Venue: Seminar Room #160
Event Official Language: English

Seminar
Mean dimension of dynamical systems and information theory
October 21 (Mon)  23 (Wed), 2019
Masaki Tsukamoto (Professor, Kyushu University)
Oct.21 15:3016:30, 16:4017:40, Okochi Hall Oct.22 13:3014:30, room #435437, Main Research Building Oct.23 13:3014:30, room #435437, Main Research Building
Venue: Okochi Hall / #435437, Main Research Building
Event Official Language: Japanese
96 events in 2019
Events
Categories
series
 iTHEMS Colloquium
 MACS Colloquium
 iTHEMS Seminar
 iTHEMS Math Seminar
 DMWG Seminar
 iTHEMS Biology Seminar
 iTHEMS Theoretical Physics Seminar
 Information Theory SG Seminar
 Quantum Matter Seminar
 ABBLiTHEMS Joint Astro Seminar
 MathPhys Seminar
 Quantum Gravity Gatherings
 RIKEN Quantum Seminar
 Quantum Computation SG Seminar
 DEEPIN Seminar
 NEW WG Seminar
 LabTheory Standing Talks
 QFTcore Seminar
 STAMP Seminar
 QuCoIn Seminar
 Number Theory Seminar
 BerkeleyiTHEMS Seminar
 iTHEMSRNC Meson Science Lab. Joint Seminar
 AcademicIndustrial Innovation Lecture
 RIKEN Quantum Lecture
 Theory of Operator Algebras
 iTHEMS Intensive CourseEvolution of Cooperation
 Introduction to PublicKey Cryptography
 Knot Theory
 iTHES Theoretical Science Colloquium
 SUURICOOL Seminar
 iTHES Seminar