I am Kazu Ghalamkari(ガラムカリ和), a postdoc in RIKEN, Japan.
Recently, I have been working with Prof. Kawahara at Osaka University. I am interested in developing methods to analyze higher-order correlations hidden in data.

I like mathematics, machine learning, programming, movies and coffee!
CV is available here.

Research Interests

Tensor Decomposition, Non-negative Matrix Factorization, Information Geometry, Machine Learning Theory


2020.4 – now JSAI (The Japanese Society for Artificial Intelligence)
2017.3 – 2018.3 JPS (The Physical Society of Japan)


Structured Learning Team,
Center for Advanced Intelligence Project (AIP)


Osaka University, Graduate School of Information Science and Technology, A410
E-mail: kazu.ghalamkari [at_mark] riken.jp


2023.04 – 2026.03Special Postdoctoral Researcher
Structured Learning Team
Center for Advanced Intelligence Project (AIP)
2020.04 – 2023.03Ph.D. student / Senior Research Assistant
National Institute of Informatics
The Graduate University for Advanced Studies
2018.04 – 2020.03Researcher
Intelligent Media Processing Group
Research & Development Group, Hitachi, Ltd.
2016.04 – 2018.03Graduate Student
Theoretical Condensed Matter and Statistical Physics Group
Department of Physics, Graduate School of Science
Tohoku University
2012.04 – 2016.03Undergraduate Student
Department of Physics, Undergraduate School of Science
Gakushuin University

External Stay

2023.09 – 2023.11Guest Postdoc
Department of Applied Mathematics and Computer Science
Cognitive Systems
Technical University of Denmark
2021.11 – 2022.04Academic Guest
Department of Biosystems Science and Engineering
Machine Learning & Computational Biology Lab
ETH Zürich

Academic degree

🎓 Doctor of Philosophy in informatics, The Graduate University for Advanced Studies, 2023.3.24
Thesis: Convex Manifold Approximation for Tensors
Committee: Prof. Mahito Sugiyama (chair), Prof. Yuichi Yoshida, Prof. Katsumi Inoue, Prof. Kazushi Mimura, Prof. Makoto Yamada


  • Convex Manifold Approximation for Tensors [pdf] [Slide]
    Doctoral thesis, The Graduate University for Advanced Studies (2023.3.24)
  • Valley polarization in layer material by light absorption [pdf] [Abst] [Slide]
    Master thesis, Graduate School of Science and Faculty of Science (2018.3)
  • 傾いたディラックコーンにおける磁場中のエネルギー準位構造 [Abst] [Slide]
    Bachelor thesis presentation, School of Science, Gakushuin University (2016.3)

💵 Grants and fellowships (PI)

  1. Danish Data Science Academy, Postdoc Fellowship 2024
    NTN-C3: Nonnegative Tensor Networks — Identifying the Limits of Convexity, Gains of Complexity, and Merits of Certainty
    1,260,000 DKK (incl. Salary)
  2. 2024.7 – 2025.3 National Institute of Informatics Open Collaborative Research 2024
    Unified solver for non-negative tensor factorization
    650,000 JPY
  3. 2023.6 – 2024.3 AIP Challenge Program
    Quantum Multi-Body Modeling of Non-Negative Tensors
    1,000,000 JPY
  4. 2023.4 – 2026.3 RIKEN, Special Postdoctoral Researchers Program
    Graph Low-rank Decomposition
    Host researcher: Prof. Yoshinobu Kawahara, Osaka Univ.
    3,000,000 JPY + Salary
  5. 2021.09 – 2021.03 日本学術振興会 第2回 若手研究者海外挑戦プログラム
    情報幾何学に基づくテンソル多体相互作用解析とバイオインフォマティクスへの応用 (declined)
    Host researcher: Prof. Karsten BORGWARDT, ETH Zürich
  6. 2021.10 – 2022.04 Young Researchers’ Exchange Programme between Japan and Switzerland 2021
    Tensor based many-body interaction analysis by information geometry and its applications to bioinformatics
    Host researcher: Prof. Karsten BORGWARDT, ETH Zürich
    Travel fee + financial support (15000 CHF)
  7. 2020.04 – 2023.03 Research Fellowship for Young Scientists (DC1)
    An information-geometric approach to quantum statistical physics using log-linear models on posets
    Host researcher: Prof. Mahito Sugiyama, SOKENDAI
    3,100,000 JPY + Salary

👑 Awards

  • 👑 AIP Network Laboratory Director Award
    AIPチャレンジプログラム AIPネットワークラボ長賞 2024.3.4
  • 👑 JSAI Annual Conference Award 2023 🔗
    人工知能学会全国大会(第37回)優秀賞 2023.11.1
  • 🎓 School of Multidisciplinary Science Dean’s Award
    総合研究大学院大学 複合科学研究科長賞 2023.3.24
  • 👑 Best Student Award, National Institute of Informatics
    国立情報学研究所優秀学生賞 2022.9.22
  • 👑 JSAI Annual Conference Award 2021 🔗
    人工知能学会全国大会(第35回)優秀賞 2021.11.1
  • 💵 Exemption from Repayment with Outstanding Achievements
    Japan Student Services Organization 2018.3
    日本学生支援機構奨学金 特に優れた業績による返還免除(全額)

RA, TA and Scholarships

  • 💵 The ANRI Fellowship 🔗
  • 👨‍🔬 Senior Research Assistant
    2020.4 – 2023.3 National Institute of Informatics
  • 👨‍🏫 Teaching Assistant: Information science I
    2016.9 – 2017.3 Faculty of Science, Tohoku University


Python5 yearsChainer, sklearn, openCV for research.
Julia3 yearsNumerical calculation
Mathematica6 yearsWolfram Language for formula processing.
Fortran90half-yearNumerical calculation
C/C++2 yearsNumerical calculation
Linux6 yearsUbuntu for development

Professional Activities

  • 2023
    • AIPチャレンジ 企画運営メンバー
  • 2022
    • 人工知能学会 基本問題研究会(SIG-FPAI研究会) サポートスタッフ 2022.9.27-30

📝 Reviews

  • 2024
    • IEEE Transactions on Signal Processing
  • 2023
    • Conference on Neural Information Processing Systems 2023 (NeurIPS2023) [Top Reviewer 🔗]
  • 2022
    • Journal of Machine Learning Research (JMLR)
    • Artificial Intelligence and Statistics Conference 2022 (AISTATS2022)
  • 2021
    • Journal of Machine Learning Research (JMLR)
    • Artificial Intelligence and Statistics Conference 2021 (AISTATS2021)