Okuto Morikawa

Profile Information

Affiliation

Special Postdoctoral Researcher, Center for Interdisciplinary Theoretical and Mathematical Sciences (iTHEMS), RIKEN

Degree

Ph.D. in Physics(Mar, 2021, Kyushu University)

Researcher number

41000334

ORCID iD

https://orcid.org/0000-0002-0044-4491

J-GLOBAL ID

202001002638083611

researchmap Member ID

R000002168

External link

https://sites.google.com/view/o-morikawa/home

Research Interests

• Quantum resonance
• Generalized symmetry
• Lattice field theory
• Conformal field theory
• Quantum field theory
• Theoretical particle physics

Research Areas

• Natural sciences / Theoretical studies related to particle-, nuclear-, cosmic ray and astro-physics /

Research History

• Apr, 2025 - Present

  Part-time Lecturer, Faculty of Engineering, Takushoku University
• Apr, 2025 - Present

  Special Postdoctoral Researcher, Center for Interdisciplinary Theoretical and Mathematical Sciences (iTHEMS), RIKEN
• Feb, 2025 - Mar, 2025

  Visiting Researcher, Department of Mathematical Sciences, Durham University
• Apr, 2024 - Mar, 2025

  Special Postdoctoral Researcher, Interdisciplinary Theoretical and Mathematical Sciences Program (iTHEMS), RIKEN
• Oct, 2023 - Mar, 2024

  Specially Appointed Researcher, Graduate School of Science, Osaka University
• Apr, 2021 - Mar, 2024

  Postdoctoral Fellow of Japan Society for the Promotion of Science, Graduate School of Science, Osaka University
• Apr, 2018 - Mar, 2021

  Research Fellow of Japan Society for the Promotion of Science, Graduate School of Science, Kyushu University

Education

• Apr, 2018 - Mar, 2021

  Department of Physics, Graduate School of Science, Kyushu University
• Apr, 2016 - Mar, 2018

  Department of Physics, Graduate School of Science, Kyushu University
• Apr, 2012 - Mar, 2016

  Department of Physics, School of Science, Kyushu University
• Apr, 2009 - Mar, 2012

  Aichi Prefectural Shinkawa High School

Committee Memberships

• 2026 - Present

  Reviewer for Mathematical Reviews (MathSciNet), American Mathematical Society
• 2025 - Present

  Reviewer, RIKEN Scientists’ Assembly Steering Committee
• 2025 - Present

  Guest Editor, International Journal of Modern Physics A

Awards

• Sep, 2026

  Particle Physics Medal: Young Scientist Award in Theoretical Particle Physics, Japan Particle and Nuclear Theory Forum

  Okuto Morikawa, Shoya Ogawa
• Sep, 2024

  Seitaro Nakamura Prize, Soryushi Shogakukai

  Okuto Morikawa
• Mar, 2024

  Young Scientist Award of the Physical Society of Japan, The Physical Society of Japan

  Okuto Morikawa
• Mar, 2023

  PTEP Editors' Choice Award, Fractional topological charge in lattice Abelian gauge theory, The Physical Society of Japan

  Motokazu Abe, Okuto Morikawa, Hiroshi Suzuki
• Sep, 2021

  Particle Physics Medal: Young Scientist Award in Theoretical Particle Physics, Japan Particle and Nuclear Theory Forum

  Okuto Morikawa, Hiromasa Takaura
• Jan, 2021

  11th Ikushi Prize, Japan Society for the Promotion of Science

  Okuto Morikawa
• Mar, 2012

  Excellence Award of Shinkawa High School, Aichi Prefectural Shinkawa High School

  Okuto Morikawa

Papers

• Complex scaling approach to quasinormal modes of Schwarzschild and Reissner--Nordström black holes

  Shoya Ogawa, Takuya Hirose, Okuto Morikawa

  PTEP, Apr 22, 2026 Peer-reviewed
• Preface

  Okuto Morikawa, Osamu Fukushima

  International Journal of Modern Physics A, 41(07) 2602001, Mar 10, 2026 Peer-reviewed
• Direct numerical simulation of the 't Hooft partition function and (de)confining phases

  Okuto Morikawa, Hiroshi Suzuki

  PoS, LATTICE2025 182, Jan 28, 2026 Peer-reviewed
• Geometric phase from encircling an exceptional point of a quantum resonance in the complex-scaling method

  Okuto Morikawa, Shoya Ogawa, Soma Onoda

  PRA, 113 052225, Dec 31, 2025 Peer-reviewed
• Exact WKB method for radial Schrödinger equation

  Okuto Morikawa, Shoya Ogawa

  JPhysA, 59 145202, Oct 13, 2025 Peer-reviewed
• Eigenstate Thermalization Hypothesis with projective representation

  Soma Onoda, Osamu Fukushima, Ryusuke Hamazaki, Okuto Morikawa

  JHEP, 06 138, Sep 2, 2025 Peer-reviewed
• On continuum and resonant spectra from exact WKB analysis

  Okuto Morikawa, Shoya Ogawa

  JPhysA, 59 225306, Aug 11, 2025 Peer-reviewed
• Unified exact WKB framework for resonance -- Zel'dovich/complex-scaling regularization and rigged Hilbert space

  Okuto Morikawa, Shoya Ogawa

  JHEP, 10 049, May 5, 2025 Peer-reviewed
• Nonperturbative Formulation of Resonances in Quantum Mechanics Based on Exact WKB Method

  Okuto Morikawa, Shoya Ogawa

  PTEP, 2025(10) 103B01, Mar 24, 2025 Peer-reviewed
• Novel Lattice Formulation of 2D Chiral Gauge Theory via Bosonization

  Okuto Morikawa, Soma Onoda, Hiroshi Suzuki

  PoS, LATTICE2024 363, Jan 31, 2025 Peer-reviewed
• Numerical simulation of fractional topological charge in $SU(N)$ gauge theory coupled with $\mathbb{Z}_N$ 2-form gauge fields

  Motokazu Abe, Okuto Morikawa

  PoS, LATTICE2024 380, Jan 20, 2025 Peer-reviewed
• Direct Monte Carlo computation of the 't~Hooft partition function

  Okuto Morikawa, Hiroshi Suzuki

  PTEP, 2025(6) 063B04, Jan 13, 2025 Peer-reviewed
• Monte Carlo simulation of the $SU(2)/\mathbb{Z}_2$ Yang--Mills theory

  Motokazu Abe, Okuto Morikawa, Hiroshi Suzuki

  PTEP, 2025(6) 063B03, Dec 31, 2024 Peer-reviewed
• Lattice study of RG fixed point based on gradient flow in 3ドル$D $O(N)$ sigma model

  Okuto Morikawa, Mizuki Tanaka, Masakiyo Kitazawa, Hiroshi Suzuki

  PoS, LATTICE2024 349, Oct 25, 2024 Peer-reviewed
• Yet another lattice formulation of 2D $U(1)$ chiral gauge theory via bosonization

  Okuto Morikawa, Soma Onoda, Hiroshi Suzuki

  PTEP, 2024(6) 063B01, Mar 6, 2024 Peer-reviewed
• Erratum to: Higher-group structure in lattice Abelian gauge theory under instanton-sum modification

  Naoto Kan, Okuto Morikawa, Yuta Nagoya, Hiroki Wada

  EPJC, 84(1) 22, Jan 9, 2024 Peer-reviewed
• Lattice realization of the axial $U(1)$ non-invertible symmetry

  Yamato Honda, Okuto Morikawa, Soma Onoda, Hiroshi Suzuki

  PTEP, 2024(4) 043B04, Jan 2, 2024 Peer-reviewed
• Lattice construction of mixed 't Hooft anomaly with higher-form symmetry

  Motokazu Abe, Okuto Morikawa, Soma Onoda, Hiroshi Suzuki, Yuya Tanizaki

  PoS, LATTICE2023 361, Dec 31, 2023 Peer-reviewed
• Higher-group symmetry in lattice gauge theories with restricted topological sectors

  Motokazu Abe, Naoto Kan, Okuto Morikawa, Yuta Nagoya, Soma Onoda, Hiroki Wada

  PoS, LATTICE2023 365, Oct 3, 2023 Peer-reviewed
• Magnetic operators in 2D compact scalar field theories on the lattice

  Motokazu Abe, Okuto Morikawa, Soma Onoda, Hiroshi Suzuki, Yuya Tanizaki

  PTEP, 2023(7) 073B01, Apr 28, 2023 Peer-reviewed

Misc.

• Two Languages for the Same Resonance: From Nuclear Decay to Black-Hole Ringdown

  Okuto Morikawa

  Aug 30, 2026
• Riesz--Laurent representation of black-hole scattering and sourced response at exceptional points

  Okuto Morikawa, Shoya Ogawa, Takuya Hirose

  Aug 14, 2026
• Numerical Hints for Dyon Condensation at $θ=2π$ via Wilson-'t Hooft Loops in $SU(2)$ Yang-Mills Theory

  Hiromasa Watanabe, Issaku Kanamori, Okuto Morikawa, Yuki Nagai, Yuya Tanizaki, Akio Tomiya

  Jun 11, 2026
• Quasinormal modes and continuum response of de Sitter black holes via complex scaling method

  Shoya Ogawa, Okuto Morikawa, Takuya Hirose

  May 5, 2026
• Unified exact WKB framework for quantum mechanical resonance

  Okuto Morikawa, Shoya Ogawa

  Meeting Abstracts of the Physical Society of Japan, 80(2) ROMBUNNO.19aEK201-10, Sep, 2025
• Gradient flow for winding numbers in real-space representation

  Takahiro Fukui, Okuto Morikawa, Hiroshi Suzuki

  Meeting Abstracts of the Physical Society of Japan, 80(2) ROMBUNNO.16aSK310-10, Sep, 2025
• Eigenstate Thermalization Hypothesis with Projective Representation

  Osamu Fukushima, Ryusuke Hamazaki, Okuto Morikawa, Soma Onoda

  Meeting Abstracts of the Physical Society of Japan, 80(2) ROMBUNNO.16aEK201-9, Sep, 2025
• Lattice non-perturbative understanding of generalized symmetries and applications

  Okuto Morikawa

  Meeting Abstracts of the Physical Society of Japan, 80(1) ROMBUNNO.18aS1-2, Mar, 2025 Invited
• Winding number on 3D lattice

  Okuto Morikawa, Hiroshi Suzuki

  Dec 5, 2024
• Yet another lattice formulation of 2D U(1) chiral gauge theory via bosonization

  Okuto Morikawa, Soma Onoda, Hiroshi Suzuki

  Meeting Abstracts of the Physical Society of Japan, 79(2) ROMBUNNO.16pWB102-6, Sep, 2024
• Non-perturbative formulation of quasi-stationary resonant state based on exact WKB method

  Okuto Morikawa, Shoya Ogawa

  Meeting Abstracts of the Physical Society of Japan, 79(2) ROMBUNNO.18pWB101-16, Sep, 2024
• Studies on generalized symmetries in lattice field theory

  Okuto Morikawa

  Meeting Abstracts of the Physical Society of Japan, 79(1) ROMBUNNO.18aS1-8, Mar, 2024 Invited
• Higher-group symmetry in lattice gauge theories with restriction of instanton numbers

  Motokazu Abe, Naoto Kan, Okuto Morikawa, Yuta Nagoya, Soma Onoda, Hiroki Wada

  Meeting Abstracts of the Physical Society of Japan, 78(2) ROMBUNNO.16aRA23-9, Sep, 2023
• Lattice formulation of magnetic operators in 2D compact scalar theories

  Motokazu Abe, Okuto Morikawa, Soma Onoda, Hiroshi Suzuki, Yuya Tanizaki

  Meeting Abstracts of the Physical Society of Japan, 78(2) ROMBUNNO.16aRA23-8, Sep, 2023
• Fractional topological charge in 4ドル$d lattice $SU(N)$ gauge theory

  Motokazu Abe, Okuto Morikawa, Soma Onoda, Hiroshi Suzuki, Yuya Tanizaki

  Meeting Abstracts of the Physical Society of Japan, 78(2) ROMBUNNO.16aRA23-7, Sep, 2023
• Constraints on the phase structure of linear quiver gauge theories from anomalies for one-form symmetries

  Okuto Morikawa, Hiroki Wada, Satoshi Yamaguchi

  Meeting Abstracts of the Physical Society of Japan, 77(2) ROMBUNNO.6pA132-12, Sep, 2022
• Analysis of Fixed Point in 3-Dimensional O(N) Scalar Model Using Gradient Flow

  Mizuki Tanaka, Masakiyo Kitazawa, Okuto Morikawa, Hiroshi Suzuki

  Meeting Abstracts of the Physical Society of Japan, 77(1) ROMBUNNO.15pA132-10, Mar, 2022
• Identification of perturbative ambiguity canceled against bion

  Okuto Morikawa, Hiromasa Takaura

  Meeting Abstracts of the Physical Society of Japan, 75(2) ROMBUNNO.14pSA-2, Sep, 2020
• Continuum extrapolation and precision measurement of the scaling dimension in the N=2 Landau-Ginzburg model

  Okuto Morikawa

  Meeting Abstracts of the Physical Society of Japan, 74(2) ROMBUNNO.18aS31-1, Sep, 2019

Presentations

• 4

  Complex scaling approach to black-hole quasinormal modes and continuum response

  Okuto Morikawa

  YITP Workshop 場の理論と弦理論 2026, Aug 18, 2026
• 4

  Dyon Condensation at $\theta=2\pi$ from Wilson-'t Hooft Loops in Yang-Mills Theory

  Hiromasa Watanabe, Issaku Kanamori, Okuto Morikawa, Yuki Nagai, Yuya Tanizaki, Akio Tomiya

  The 43rd International Symposium on Lattice Field Theory (Lattice2026), Jul 29, 2026
• 1

  Towards a nonperturbative formulation of non-Hermitian quantum physics

  Okuto Morikawa

  Particle-Physics Endeavor Across Kyushu (P^2EAK), Jul 20, 2026 Invited
• 12

  Lattice 2D $U(1)$ chiral gauge theory and magnetically charged vertex operators via bosonization

  Okuto Morikawa

  Frontiers of Lattice Fermions, Jul 2, 2026 Invited
• 10

  Geometric phase of exceptional point as quantum resonance in complex scaling method

  Okuto Morikawa, Shoya Ogawa, Soma Onoda

  2026 Spring Meeting of the Physical Society of Japan, Mar 23, 2026
• 10

  Complex Analytic Structure and Resurgence in the Radial Schrödinger Equation

  Okuto Morikawa, Shoya Ogawa

  2026 Spring Meeting of the Physical Society of Japan, Mar 23, 2026
• Infrared Renormalons, Bion Ambiguities, and Resurgence in Compactified Gauge Theories

  Okuto Morikawa

  Seminar at Takushoku University, Mar 17, 2026 Invited
• 19

  Towards a nonperturbative formulation of non-Hermitian quantum physics: resonance, complex scaling, and resurgence analysis

  Okuto Morikawa

  Seminar at Takushoku University, Jan 21, 2026 Invited
• 28

  Unified exact WKB framework for quantum resonance and scattering theory

  Okuto Morikawa

  KEK Theory Workshop 2025, Dec 16, 2025
• 31

  Aspects of Quantum Resonance Revisited

  Okuto Morikawa

  iTHEMS Coffee Meeting Talk, Dec 12, 2025
• Study of confinement phase based on lattice QCD simulation

  Okuto Morikawa

  Ikushi Prize Laureates’ Networking Meeting, Nov 28, 2025
• 56

  What is quantum resonance? -a viewpoint from resurgence theory-

  Okuto Morikawa

  Seminar at Theoretical Particle Physics Group in Kobe University, Nov 26, 2025 Invited
• 32

  Exact WKB framework for quantum resonance and spectral theory

  Okuto Morikawa

  Seminar at Theoretical Particle Physics Group in Tohoku University, Nov 21, 2025 Invited
• 31

  Direct numerical simulation of 't Hooft partition function and (de)confining phase

  Okuto Morikawa, Hiroshi Suzuki

  The 42nd International Symposium on Lattice Field Theory (Lattice2025), Nov 4, 2025
• 38

  Non-perturbative Confirmation of the Wilson-Fisher Fixed Point via Gradient Flow in 3D O(N) Sigma Model

  Okuto Morikawa

  Seminar at Theoretical Particle Physics Group in Kyoto University, Oct 29, 2025 Invited
• 42

  Resonances, Spectral Theory, and the Resurgent Structure

  Okuto Morikawa

  Japan-UK Workshop on Quantum Gravity, Sep 23, 2025 Invited
• 33

  Unified exact WKB framework for quantum mechanical resonance

  Okuto Morikawa, Shoya Ogawa

  2025 Annual (80th) Meeting of the Physical Society of Japan, Sep 19, 2025
• 41

  Non-perturbative analysis of resonance physics by exact WKB method

  Okuto Morikawa

  Finite temperature field theory and its application 2025 (TQFT 2025), Sep 5, 2025
• 44

  Non-perturbative understanding of resonant phenomena based on exact WKB analysis

  Okuto Morikawa

  Strings and Fields 2025, Aug 1, 2025
• Lattice simulation of Wilson--'t~Hooft classification in $SU(2)$ Yang--Mills theory with $\theta$ term

  Issaku Kanamori, Okuto Morikawa, Yuki Nagai, Yuya Tanizaki, Akio Tomiya, Hiromasa Watanabe

  iTHEMS Now&Next 2025, Jul 24, 2025

Teaching Experience

• Apr, 2026 - Sep, 2026

  Science Laboratory (Takushoku University)
• Apr, 2026 - Sep, 2026

  Physics I (Takushoku University)
• Oct, 2025 - Mar, 2026

  Science Laboratory (Takushoku University)
• Oct, 2025 - Mar, 2026

  Physics II (Takushoku University)
• Apr, 2025 - Sep, 2025

  Science Laboratory (Takushoku University)
• Apr, 2025 - Sep, 2025

  Physics I (Takushoku University)

Professional Memberships

• Japan Particle and Nuclear Theory Forum
• The Physical Society of Japan

Works

• CSMQNM.jl: skeleton for computing black-hole quasinormal-mode candidates with the complex scaling method

  Shoya Ogawa, Okuto Morikawa

  May 5, 2026 Software
• AutoTortoise.jl: horizon-aware tortoise-coordinate construction for static spherically symmetric black-hole metrics

  Okuto Morikawa

  May 5, 2026 Software
• Wind3D: Discrete approximation to 3D winding number mapping T^3->U(N)

  Okuto Morikawa

  Dec 4, 2024 Software
• ErrorEst.jl: Tools for julia programming of statistical analysis

  Okuto Morikawa

  Dec, 2024 Software
• HigherCup: Symbolic manipulation of Steenrod higher cups

  Okuto Morikawa

  Dec, 2024 Software
• HigherBfields.jl: Utilities of gauge fields coupled with higher-form gauge fields

  Okuto Morikawa

  Aug, 2024 Software
• Gaugefields.jl: Utilities of quantum theory of (higher-form) general gauge fields

  Okuto Morikawa

  Jun 25, 2024 Software
• Resummation: Some resummation techniques based on perturbation theory

  Okuto Morikawa

  2022 Software
• LandauGinzburg: C++ codeset for simulation of N=2 Landau-Ginzburg model

  Okuto Morikawa

  2021 Software

Research Projects

• Rigorous formulation of the generalized symmetries from the viewpoint of lattice gauge theory

  Grants-in-Aid for Scientific Research Grant-in-Aid for Early-Career Scientists, Grant-in-Aid for Early-Career Scientists, Japan Society for the Promotion of Science, Apr, 2025 - Mar, 2030

  Okuto Morikawa
• Exceptional Points in Nuclear Reactions: From Resonance Poles to Observable Line Shapes

  COREnet project of RCNP, The University of Osaka, Apr, 2026 - Mar, 2028
• Gradient flow for solving the over-smearing problem of topological charge

  Multidisciplinary Cooperative Research Program 2025, University of Tsukuba, Apr, 2025 - Mar, 2027
• Resurgence and non-perturbative formulation of resonances in quantum theory

  FY2025 Incentive Research Projects, RIKEN, Apr, 2025 - Mar, 2027

  Okuto Morikawa
• Rigorous formulation of the generalized symmetries from the viewpoint of lattice gauge theory

  Special Postdoctoral Researcher Program, RIKEN, Apr, 2024 - Mar, 2027

  Okuto Morikawa
• Nonperturbative method for quantum field theory and its application to superstring theory

  Grants-in-Aid for Scientific Research Grant-in-Aid for JSPS Fellows, Grant-in-Aid for JSPS Fellows, Japan Society for the Promotion of Science, Mar, 2023 - Mar, 2024

  Okuto Morikawa
• Nonperturbative method for quantum field theory and its application to superstring theory

  Grants-in-Aid for Scientific Research Grant-in-Aid for JSPS Fellows, Grant-in-Aid for JSPS Fellows, Japan Society for the Promotion of Science, Apr, 2021 - Mar, 2024

  Okuto Morikawa
• Nonperturbative approach to field theory and superstring theory

  Grants-in-Aid for Scientific Research Grant-in-Aid for JSPS Fellows, Grant-in-Aid for JSPS Fellows, Japan Society for the Promotion of Science, Apr, 2018 - Mar, 2021

  Okuto Morikawa

Academic Activities

• GRAPPA-QFT Seminar Series

  Planning, management, etc., Panel moderator, session chair, etc.

  Okuto Morikawa, 2024 - Present
• Referee Report on "A discrete formulation for three-dimensional winding number," SciPost Phys. Core 9, 026 (2026)

  Peer review

  SciPost Foundation, Apr 9, 2026
• Session chair, 2025 Annual (80th) Meeting of the Physical Society of Japan

  Panel moderator, session chair, etc.

  The Physical Society of Japan, Sep 16, 2025 - Sep 19, 2025
• Session chair, Strings and Fields 2025

  Panel moderator, session chair, etc.

  YITP, Kyoto University, Jul 28, 2025 - Aug 1, 2025
• Kyushu IAS-iTHEMS conference: Non-perturbative methods in QFT

  Planning, management, etc., Panel moderator, session chair, etc., Peer review

  (Kyushu University Institute for Advanced Study), Mar 10, 2025 - Mar 14, 2025
• Session chair, 2024 Annual (79th) Meeting of the Physical Society of Japan

  Panel moderator, session chair, etc.

  The Physical Society of Japan, Sep 16, 2024 - Sep 19, 2024
• Session chair, the 40th International Symposium on Lattice Field Theory (Lattice2023)

  Panel moderator, session chair, etc.

  Jul 31, 2023 - Aug 4, 2023
• Session chair, 2021 Autumn Meeting of the Physical Society of Japan

  Panel moderator, session chair, etc.

  The Physical Society of Japan, Sep 14, 2021 - Sep 17, 2021
• Session chair, YONUPA Summer School 2020

  Panel moderator, session chair, etc.

  Aug 26, 2020 - Aug 28, 2020
• SciPost Physics Core, Referee

  Peer review

  SciPost Foundation
• J. High Energy Phys., Referee

  Peer review

  Springer
• Next Research, Referee

  Peer review

  Elsevier

Social Activities

• Nonperturbative formulation of resonances in quantum mechanics based on exact WKB method

  Official expert, Contributor

  Wolfram Research, Wolfram Community, Feb 7, 2026
• Mathematical Exchange Platform Bridging RIKEN and Kyoto University MACS

  Lecturer

  Kyoto University MACS, Dec, 2025
• Interview Survey of JSPS Ikushi Prize

  Filming support, Consultant, Official expert

  Osaka University, Mar, 2022

Media Coverage

• Wolfram Community Staff Picks (Featured Contributor Badge), Editorial selection / featured post

  Wolfram Research, Wolfram Community, Feb, 2026 Internet
• Fractional Topological Charge in Abelian Lattice Gauge Theory

  The Physical Society of Japan, JPS Magazine BUTSURI, Recent Featured Papers in PTEP, Jul, 2023 Promotional material
• Fractional Topological Charge Construction in a U(1) Lattice Gauge Theory Framework

  The Physical Society of Japan, JPS Hot Topics, Mar 27, 2023

Other

• Representative of the graduates (PhD), Kyushu University

  Mar, 2021

  Valedictory speech (in Japanese only) https://youtu.be/DaorDMritQs
• JASSO Scholarship "Exemption from Return for Particularly Outstanding Achievement", Japan Student Services Organization (JASSO)

  Apr, 2016 - Mar, 2018
• Representative of the graduates (Bachelor of Science), Kyushu University

  Mar, 2016
• Kyushu University Honors Scholarship, Kyushu University

  Oct, 2014 - Mar, 2015
• Kyushu University Honors Scholarship, Kyushu University

  Apr, 2014 - Sep, 2014