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Photos by Sugumi Kanno @ Einstein Museum
Our research group explores cosmology and gravitational theory using quantum information theory. We are theoretically investigating fundamental questions such as “How did the universe begin and evolve?” and “Is it possible to unify gravity and quantum theory?”
In cosmology, we focus on primordial gravitational waves generated in the early universe and the nature of dark matter. In gravitational theory, we address foundational problems concerning the consistency between gravity and quantum field theory. (Click here for more details on our research.)
Our group consists of 4 faculty members, 2 doctoral students, 6 master's students, and 4 undergraduate students. (Click here for more details about members.)
Recent News
Mar 31, 2026
Mar 31, 2026
Our paper appears on arXiv.
Tomoya Hirotani, Akira Matsumura
"Testing classical-quantum gravity with geodesic deviation''
Mar 27, 2026
Mar 27, 2026
Our paper appears on arXiv.
Giuseppe Fabiano, Tomohiro Fujita, Akira Matsumura, Daniel Carney
"Minimal noise in non-quantized gravity''
Mar 25, 2026
Masaki Tani, Yuta Uenaga, Kosei Hatakeyama, Tomoya Hirotani and Ryotaro Fukuzumi have obtained their Master’s degrees in Science. Shogo Higuma, Kota Fujii and Takeaki Murata have obtained their bachelor’s degrees in Science.
Masaki Tani will get a job at a company, and Yuta Uenaga, Kosei Hatakeyama, Tomoya Hirotani and Ryotaro Fukuzumi will continue their research in our laboratory as doctoral students. Shogo Higuma, Kota Fujii and Takeaki Murata will also continue their research as master students.
The image is from HP of The Physical Society of Japan 2026 Annual Meeting.
Mar 23 - 26, 2026
Yuta Uenaga and Taiki Ikeda made oral presentations in The Physical Society of Japan 2026 Annual Meeting held online.
Mar 17, 2026
Mar 17, 2026
Our paper appears on arXiv.
Kosei Hatakeyama, Ryotaro Fukuzumi, Akira Matsumura, Daisuke Miki, Kazuhiro Yamamoto
"Measurement-Based Estimation of Causal Conditional Variances and Its Application to Macroscopic quantum phenomenon''
The image is from HP of Concepts of Quantum and Spacetime.
Mar 9 - 12, 2026
Akira Matsumura talked as an invited speaker and Tomoya Hirotani made a poster presentation in Concepts of Quantum and Spacetime held at KEK.
The image is from HP of Quantum Foundations.
Mar 5 - 6, 2026
Takano Taira, Yuta Uenaga, Tomoya Hirotani made poster presentations in Quantum Foundations held at Osaka University.
Feb 13, 2026
The research result was released by Kyushu University.
Press release : The quantum nature hidden in gravitational waves from binary black holes ~A first step towards quantum gravity theory~
Feb 12, 2026
Feb 12, 2026
The paper was published in Physical Review Letters.
Sugumi Kanno, Jiro Soda, Akira Taniguchi
"Coherent State Description of Gravitational Waves from Binary Black Holes"
Feb 2, 2026
Feb 2, 2026
Our paper appears on arXiv.
Kaito Kashiwagi, Akira Matsumura
"Gravitational effects on a dissipative two-level atom in the weak-field regime''
Jan 28, 2026
Jan 28, 2026
Our paper appears on arXiv.
Kimihiro Nomura, Akira Taniguchi, Kazushige Ueda
"Violation of the Leggett-Garg inequality in photon-graviton conversion''
Jan 23, 2026
Akira Taniguchi received Outstanding Presentation Award Gold Prize at The 34th Workshop on General Relativity and Gravitation in Japan (JGRG 34).
Tiltle: Quantum nature of gravitational waves from binary black holes and its applications to cosmology
The photo is from HP of JGRG 34.
Jan 19 - 23, 2026
Akira Matsumura, Kaito Kashiwagi, Akira Taniguchi, Yuta Uenaga, Kosei Hatakeyama, Ryotaro Fukuzumi, Tomoya Hirotani and Taiki Ikeda gave oral presentations at The 34th Workshop on General Relativity and Gravitation in Japan (JGRG 34) held at Kyoto University.
Jan 15, 2026
Jan 15, 2026
Our research was featured in the Quantum and Spacetime Research Institute.
Article：Squeezed Light Enhances the Sensitivity of Experiments Probing Gravity-Induced Entanglement
Dec 20, 2025
In the 131st Kyushu Branch Meeting of the Physical Society of Japan held at Sojo University, Takano Taira, Yuta Uenaga and Taiki Ikeda made oral presentations.
Dec 15-17, 2025
Kaito Kashiwagi, Akira Taniguchi, Kosei Hatakeyama, Ryotaro Fukuzumi, Taiki Ikeda, and Kota Fujii made oral presentations in the Quantum and Gravity Meeting 2025.
The image is from HP of the Perspective on Time, Uncertainty and Quantum computation
Dec 9, 2025
Dec 9, 2025
Kazuhiro Yamamoto talked in the Perspective on Time, Uncertainty and Quantum computation as an invited speaker.
Title: Is Gravity Quantum? − From Thought Experiment to Optomechanical Test −
Nov 12, 2025
Nov 12, 2025
Our paper appears on arXiv.
Yuka Shiomatsu, Youka Kaku, Akira Matsumura, Tomohiro Fujita
"Boosting Gravity-Induced Entanglement through Parametric Resonance''
Oct 27, 2025
Oct 27, 2025
Our paper appears on arXiv.
Sugumi Kanno, Jiro Soda, Akira Taniguchi
"Binary gravitational waves as probes of quantum graviton states''
Oct 20, 2025
Oct 20, 2025
Tomoya Hirotani received the Student Presentation Award of the Physical Society of Japan at the Physical Society of Japan 2025 Annual Meeting.
Tiltle: Oppenheimによる相対論的半古典重力模型で予言される測地線偏差の量子ゆらぎ
The image is from HP of the COSMO-25
Oct 13 - 17, 2025
Akira Taniguchi gave an oral presentation at 28th International Conference on Particle Physics & Cosmology (COSMO-25) held at Carnegie Mellon University, Pittsburgh.
The image is from HP of the Elementary, particles, space, gravity and quantum sensing.
Oct 8 - 10, 2025
In the Elementary, particles, space, gravity and quantum sensing, Akira Matsumura talked as an invited speaker and Akira Taniguchi, Kosei Hatakeyama, Ryotaro Fukuzumi and Taiki Ikeda made oral presentations.
Oct 1, 2025
"Quantum and Spacetime Research Institute" has been founded.
Press Release: https://www.kyushu-u.ac.jp/ja/notices/view/2965
The image is from HP of Research and education at Hiroshima University's Institute of Theoretical Science.
Sep 24, 2025
Kazuhiro Yamamoto talked in the Research and education at Hiroshima University's Institute of Theoretical Science as an invited speaker.
The photo is from HP of The Physical Society of Japan 2025 Annual Meeting
Sep 16 - 19, 2025
Takano Taira, Akira Taniguchi, Yuta Uenaga, Kosei Hatakeyama, Tomoya Hirotani and Ryotaro Fukuzumi talked in The Physical Society of Japan 2025 Annual Meeting.
Contact us
Contact us
Department of Physics, Kyushu University
W1-A-720, 744, Motooka, Nishi-ku, Fukuoka, Japan, 819-0395
Phone: +81-092-802-4101
Fax: +81-092-802-4107
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