Volume 179
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Volume 179
December 17, 2021
Event Schedule
Events for the 4th week of December 2021
2021-12-16
Monday, December 20, 13:30– 15:00 NEW WG Seminar
Friday, December 24, 12:30- Coffee Meeting
Press Release
Universal chords played by black holes - Toward the verification of general relativity by black hole fluctuations
2021-12-15
Naritaka Oshita (Special Postdoctoral Researcher, iTHEMS) has revealed the "universal combination" of vibration patterns of black holes that are most easily excited from theoretical calculations.
This research result is expected to contribute to the measurement of the weight and rotation speed of black holes by observational data of space-time ripples (gravitational waves) propagating immediately after the merger of a binary black hole, and to the precise test of Einstein’s general theory of relativity.
To read more, please see the related link (in Japanese).
Reference
- Naritaka Oshita, Ease of excitation of black hole ringing: Quantifying the importance of overtones by the excitation factors, Phys. Rev. D 104, 124032 (2021), doi: 10.1103/PhysRevD.104.124032
Research News
RIKEN Research: Exotic six-quark particle predicted by supercomputers
2021-12-13
Dr. Takuya Sugiura (Postdoctoral Researcher, iTHEMS) was featured in the Research News on the RIKEN website.
The predicted existence of an exotic particle made up of six elementary particles known as quarks by RIKEN researchers could deepen our understanding of how quarks combine to form the nuclei of atoms.
To read more, please see the related links.
Reference
- Lyu, Y., Tong, H., Sugiura, T., Aoki, S., Doi, T., Hatsuda, T., Meng, J. & Miyamoto, T., Dibaryon with highest charm number near unitarity from lattice QCD, Physical Review Letters 127, 072003 (2021), doi: 10.1103/PhysRevLett.127.072003
Seminar Report
iTHEMS Math Seminar by Dr. Ryosuke Iritani on December 8, 2021
2021-12-10
On December 8, Dr. Ryosuke Iritani (iTHEMS) gave a talk in Math Seminar. He talked about expectation value of certain random variables. He and his collaborators obtained a result on its explicit formula together with an algorithm of its fast calculation.
This was the last Math Seminar talk of the year 2021. After the seminar there was an online Christmas party.
Reported by Michiya Mori
Generalized Bernoulli process and computation of proportional areas for Venn diagram
December 8 (Wed) at 16:00 - 18:00, 2021
Upcoming Event
Seminar
Quantum metric of topological and non-topological insulators in AMO and other systems
December 20 (Mon) at 13:30 - 15:00, 2021
Tomoki Ozawa (Associate Professor, Advanced Institute for Materials Research (AIMR), Tohoku University)
Recently, the concept of quantum geometry is attracting great interests in various areas of condensed matter and AMO physics. Quantum geometry tells how much the quantum states "change" as one moves in a parameter space, and is closely related to the topology of the quantum states. Quantum geometric tensor is often used to characterize the geometry, whose real part is the quantum metric and the imaginary part is the Berry curvature. Although Berry curvature is rather well-studied in the context of topological insulators and superconductors, less has been known about the quantum metric. However, experiments detecting the quantum metric have appeared in the past couple of years and interest in quantum metric is indeed growing. In this talk, I first explain basics of quantum metric and its recent experimental observations. I then discuss various aspects of quantum metric, including its relation to localization, topology, and the Kähler geometry.
References
- Tomoki Ozawa and Nathan Goldman, Extracting the quantum metric tensor through periodic driving, Phys. Rev. B 97, 201117(R) (2018), doi: 10.1103/PhysRevB.97.201117
- Tomoki Ozawa and Nathan Goldman, Probing localization and quantum geometry by spectroscopy, Phys. Rev. Research 1, 032019(R) (2019), doi: 10.1103/PhysRevResearch.1.032019
- Luca Asteria, Duc Thanh Tran, Tomoki Ozawa, Matthias Tarnowski, Benno S. Rem, Nick Fläschner, Klaus Sengstock, Nathan Goldman and Christof Weitenberg , Measuring quantized circular dichroism in ultracold topological matter, Nature Physics volume 15, pages 449–454 (2019), doi: 10.1038/s41567-019-0417-8
- Min Yu, Pengcheng Yang, Musang Gong, Qingyun Cao, Qiuyu Lu, Haibin Liu, Shaoliang Zhang, Martin B Plenio, Fedor Jelezko, Tomoki Ozawa, Nathan Goldman, Jianming Cai, Experimental measurement of the quantum geometric tensor using coupled qubits in diamond, National Science Review, Volume 7, Issue 2 (2020), doi: 10.1093/nsr/nwz193
- Tomoki Ozawa and Bruno Mera, Relations between topology and the quantum metric for Chern insulators, Phys. Rev. B 104, 045103 (2021), doi: 10.1103/PhysRevB.104.045103
- Bruno Mera and Tomoki Ozawa, Kähler geometry and Chern insulators: Relations between topology and the quantum metric, Phys. Rev. B 104, 045104 (2021), doi: 10.1103/PhysRevB.104.045104
- Bruno Mera and Tomoki Ozawa, Engineering geometrically flat Chern bands with Fubini-Study Kähler structure, Phys. Rev. B 104, 115160 (2021), doi: 10.1103/PhysRevB.104.115160
- Yu Liu, Min Yu, Pengcheng Yang, Musang Gong, Qingyun Cao, Shaoliang Zhang, Haibin Liu, Markus Heyl, Tomoki Ozawa, Nathan Goldman, Jianming Cai, Saturating the quantum Cramér-Rao bound and measuring the related quantum Fisher information in a nitrogen-vacancy center in diamond, Quantum Physics (2020), arXiv: 2003.08373
Venue: via Zoom
Event Official Language: English
Paper of the Week
Week 3, December 2021
2021-12-16
Title: Isovector density and isospin impurity in $^{40} \mathrm{Ca}$
Author: H. Sagawa, S. Yoshida, T. Naito, T. Uesaka, J. Zenihiro, J. Tanaka
arXiv: http://arxiv.org/abs/2112.06169v1
Title: Toward a resolution of the NN controversy
Author: Amy Nicholson, Evan Berkowitz, John Bulava, Chia Cheng Chang, M. A. Clark, Andrew D. Hanlon, Ben Horz, Dean Howarth, Christopher Korber, Wayne Tai Lee, Aaron S. Meyer, Henry Monge-Camacho, Colin Morningstar, Enrico Rinaldi, Pavlos Vranasc, Andre Walker-Loud
arXiv: http://arxiv.org/abs/2112.04569v1
Title: Dispersive qubit readout with machine learning
Author: Enrico Rinaldi, Roberto Di Candia, Simone Felicetti, Fabrizio Minganti
arXiv: http://arxiv.org/abs/2112.05332v1
Title: Neural quantum states for supersymmetric quantum gauge theories
Author: Xizhi Han, Enrico Rinaldi
arXiv: http://arxiv.org/abs/2112.05333v1
Title: Cooper quartet correlations in infinite symmetric nuclear matter
Author: Yixin Guo, Hiroyuki Tajima, Haozhao Liang
arXiv: http://arxiv.org/abs/2112.05349v1
Title: Global 4-group symmetry and 't Hooft anomalies in topological axion electrodynamics
Author: Yoshimasa Hidaka, Muneto Nitta, Ryo Yokokura
arXiv: http://arxiv.org/abs/2108.12564v1
Title: Dynamical quantum phase transition in a non-Hermitian Hubbard model
Author: Tomoya Hayata, Yoshimasa Hidaka, Arata Yamamoto
arXiv: http://arxiv.org/abs/2111.03893v2
Title: Lattice Lindblad simulation
Author: Tomoya Hayata, Yoshimasa Hidaka, Arata Yamamoto
arXiv: http://arxiv.org/abs/2111.04937v1
Title: Finite volume analysis on systematics of the derivative expansion in HAL QCD method
Author: Takumi Doi, Yan Lyu, Hui Tong, Takuya Sugiura, Sinya Aoki, Tetsuo Hatsuda, Jie Meng, Takaya Miyamoto
arXiv: http://arxiv.org/abs/2112.04997v1
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