Koichi Murase

Curriculum Vitae

Basic profile

• Name: MURASE, Koichi (村瀬功一)
• Nationality: Japan
• Birth: Sep. 20, 1987
• Gender: Male

Position & Affiliation

Address

Major interests

• Physics interests:
  • Dynamical process of high-energy heavy-ion collisions
    • Dynamics of quark-gluon plasma
    • Hydrodynamic fluctuations
    • Thermalization
  • Neutron-star equation of state
  • Hadron-hadron interactions
• Methods
  • Relativistic hydrodynamics
  • Kinetic theory
  • Non-equilibrium statistics
  • Machine learning
  • Lattice gauge theory

Work Experience

• Apr. 2025 - (present): Assistant Professor, Graduate School of Science, The University of Osaka
• Oct. 2025 - Mar. 2026: Specially Appointed Assistant Professor, Research Center for Nuclear Physics, The University of Osaka
  Address

  Postal address: Research Center for Nuclear Physics, The University of Osaka, 10-1, Mihogaoka, Ibaraki, Osaka 567-0047, JAPAN Room: Rm. 509 (5th floor), Main Bldg., Research Center for Nuclear Physics, Suita Campus, The University of Osaka Tel (shared): +81-6-6879-8902, ext. 8945 E-mail address: kmurase at rcnp.osaka-u.ac.jp
• Jan. 2024 - Sep. 2025: Research assistant professor, Tokyo Metropolitan University
  Address

  Postal address: Department of Physics, Tokyo Metropolitan University, 1-1, Minami-Osawa, Hachioji-shi, Tokyo, 192-0397, Japan Room: Rm. 582 (5th floor), Bldg. 8, Minami-Osawa Campus, Tokyo Metropolitan University, Tel (shared): +81-42-677-1111 (3372) E-mail address: murase at tmu.ac.jp
• Apr. 2021 - Dec. 2023: Research assistant professor, Yukawa Institute for Theoretical Physics, Kyoto University
  Address

  Postal address: K203E, Yukawa Institute for Theoretical Physics, Kyoto University, Oiwake-cho, Kitashirakawa, Sakyo-ku, Kyoto-shi, Kyoto, 606-8502, Japan Room: K203E (second floor), Yukawa Institute for Theoretical Physics, North Campus, Kyoto University Tel (shared): +81-75-753-7046 E-mail address: koichi.murase at yukawa.kyoto-u.ac.jp
• Sep. 2019 - Mar. 2021: Postdoctoral researcher, Center for High-Energy Physics, Peking University
  Address

  Heavy-ion group (Prof. Huichao Song), Center for High Energy Physics, Peking University B105 West Building, School of Physics, Peking University, No. 209, Chengfu Road, Haidian District, Beijing, 100871, People's Republic of China, Phone number (shared): +86-10-62753087 E-mail (institution): murase at pku.edu.cn
• Apr. 2018 - Aug. 2019: Project Postdoctoral Researcher, Sophia University
  
  Address

  High-energy hadron physics group (Hirano group), Department of Engineering and Applied Sciences, Faculty of Science and Technology, Sophia University Address: Room 4-286, Bldg. 4, Department of Engineering and Applied Sciences, Faculty of Science and Technology, Sophia University, 7-1 Kioicho, Chiyoda-ku, Tokyo 102-8554, Japan E-mail (institution): murase at sophia.ac.jp
• Feb. 2016 - Mar. 2018: Postdoctoral fellow, The University of Tokyo
  Address

  Hadron Theoretical Physics group (Fukushima group), Department of Physics, School of Science, The University of Tokyo Address: Room 922, Bldg. Science 1, Department of Physics, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8654, Japan E-mail (institution): murase at nt.phys.s.u-tokyo.ac.jp

Others

• Oct. 2015 - Jan. 2016: Research Part-Timer, Hadron theoretical physics group (Hirano group), Faculty of Science and Technology, Sophia University
• Apr. 2015 - Sep. 2015: Research Support Part-Timer, Quantum Hadron Physics group (Hatsuda group), Nishina Center, RIKEN
• Apr. 2012 - Mar. 2015: Research Fellowship for Young Researcher (DC1), JSPS (Japan Society for the Promotion of Science)
• Apr. 2012 - Sep. 2015: Research Trainee in Quantum Hadron Physics group (Hatsuda group), Nishina Center, RIKEN
• Apr. 2011 - Mar. 2018: Science and Technology Collaborative Researcher, High-energy hadron theoretical physics group, Department of Engineering and Applied Sciences, Faculty of Science and Technology, Sophia University
• Apr. 2010 - Mar. 2011: Teaching Assistant for Numerical Experiments, Department of Physics, School of Science, University of Tokyo

Thesis

Ph.D. Thesis - Link - PDF

• Title: Causal hydrodynamic fluctuations and their effects on high-energy nuclear collisions
• Chief examiner: Naoki Yoshida
• Examiner: Hideki Hamagaki, Masahiro Kawasaki, Masaki Sano, Osamu Morimatsu
• Degree: Ph.D. / 博士(理学), Sep. 25, 2015, The University of Tokyo

Education

• Apr. 2012 - Sep. 2015: PhD student in Department of Physics, School of Science, The University of Tokyo (supervisor: Tetsuo Hatsuda)
• Apr. 2010 - Mar. 2012: Master course student in Department of Physics, School of Science, The University of Tokyo (supervisor: Tetsufumi Hirano, Tetsuo Hatsuda)
• Apr. 2008 - Mar. 2010: Undergraduate student in Department of Physics, Faculty of Science, The University of Tokyo
• Apr. 2006 - Mar. 2008: Undergraduate student in Natural Sciences I, College of Arts and Sciences (Junior Division), The University of Tokyo
• Apr. 2003 - Mar. 2006: High school student in General course, Aichi Prefectural Asahigaoka High School

Publication/Presentation

Selected publications

• Koichi Murase, "Causal hydrodynamic fluctuations in non-static and inhomogeneous backgrounds" Annals Phys. 411, 167969 (2019) [arXiv:1904.11217 [nucl-th]]
• Yuki Fujimoto, Kenji Fukushima and Koichi Murase, "Methodology study of machine learning for the neutron star equation of state", Phys. Rev. D 98, 023019 (2018) [arXiv:1711.06748 [nucl-th]]
• Kenji Fukushima, Koichi Murase and Shi Pu, "Fixed points and flow analysis on off-equilibrium dynamics in the boson Boltzmann equation", Annals Phys. 386, 76-96 (2017) [arXiv:1703.09492 [hep-ph]]
• Koichi Murase and Tetsufumi Hirano, "Hydrodynamic fluctuations and dissipation in an integrated dynamical model", Nucl. Phys. A 956, 276-279 (2016) [arXiv:1601.02260 [nucl-th]]
• Shiori Takeuchi, Koichi Murase, Tetsufumi Hirano, Pasi Huovinen and Yasushi Nara, "Effects of hadronic rescattering on multistrange hadrons in high-energy nuclear collisions", Phys. Rev. C 92, 044907 (2015) [arXiv:1505.05961 [nucl-th]]
• Tetsufumi Hirano, Pasi Huovinen, Koichi Murase and Yasushi Nara, "Integrated Dynamical Approach to Relativistic Heavy Ion Collisions", Prog. Part. Nucl. Phys. 70, 108-158 (2013) [arXiv:1204.5814 [nucl-th]].

Others

• Koichi Murase - INSPIRE
• Search | arXiv e-print repository

Recent

• (Jun. 28, 2022) Talk (Japanese: A. Ohnishi, A. Jinno, K. Murase, Y. Nara, HYP2022 Directed flow of Lambda from heavy-ion collisions and hyperon puzzle of neutron stars, HYP2022

• (Jan. 20, 2021) Paper: Yuki Fujimoto, Kenji Fukushima, Koichi Murase, [2101.08156] Extensive Studies of the Neutron Star Equation of State from the Deep Learning Inference with the Observational Data Augmentation
• (Mar. 30, 2020) Paper: Azumi Sakai, Koichi Murase, Tetsufumi Hirano, [2003.13496] Rapidity decorrelation of anisotropic flow caused by hydrodynamic fluctuations
• (Mar. 19, 2020) Talk (Japanese): Koichi Murase, 19pK18-6 「膨張系における2次流体力学の揺動散逸関係とゆらぎの定理」 (Fluctuation-dissipation relation and fluctuation theorem of the second-order hydrodynamics in expanding systems), JPS Annual Meeting 2020, Japan (online)
• (Mar. 16, 2020) Talk (Japanese): Kenshi Kuroki, Azumi Sakai, Koichi Murase, Tetsufumi Hirano, 16aH22-5 「超中心高エネルギー重イオン衝突反応における流体揺らぎの効果」 (The effects of hydrodynamic fluctuations in ultra-central high-energy heavy-ion collisions), JPS Annual Meeting 2020, Japan (online)
• (Mar. 16, 2020) Talk (Japanese): Azumi Sakai, Koichi Murase, Tetsufumi Hirano, 16aH22-5 「流体揺らぎによる因子化の破れの衝突エネルギー依存性 」 (Collision energy dependence of factorization breaking by hydrodynamic fluctuations), JPS Annual Meeting 2020, Japan (online)
• (Jan. 16, 2020) Invited talk: Koichi Murase, Inferring nuclear matter properties from neutron star observables using deep learning, Mini-Workshop on "Localization, Many-body Physics, and Machine Learning (ML) Application to Physics Research, ICQM PKU, Beijing, China
• (Nov. 5, 2019) Talk: Azumi Sakai, Koichi Murase, Tetsufumi Hirano, Rapidity decorrelation caused by hydrodynamic fluctuations and initial longitudinal fluctuations, Quark Matter 2019, Wuhan, China
• (Nov. 4, 2019) Poster: Koichi Murase, Fluctuation-dissipation relation and fluctuation theorem for causal hydrodynamic fluctuations, Quark Matter 2019, Wuhan, China
• (Nov. 4, 2019) Poster: Kenshi Kuroki, Azumi Sakai, Koichi Murase, Tetsufumi Hirano, Effects of hydrodynamic fluctuations on azimuthal flow in ultra-central heavy-ion collisions, Quark Matter 2019, Wuhan, China
• (Nov. 4, 2019) Poster: Yuki Gogun, Azumi Sakai, Koichi Murase, Tetsufumi Hirano, Factorization breaking in transverse momentum from hydrodynamic fluctuations, Quark Matter 2019, Wuhan, China
• (Nov. 4, 2019) Poster: Yuto Yoshida, Koichi Murase, Tetsufumi Hirano, Parametrized equation of state with critical point and first-order phase transition, Quark Matter 2019, Wuhan, China
• (Oct. 30, 2019) Talk: Azumi Sakai, Koichi Murase, Tetsufumi Hirano, Rapidity decorrelation caused by hydrodynamic fluctuations and initial longitudinal fluctuations, Workshop "New Development of Hydrodynamics and its applications in Heavy-ion Collisions", Shanghai, China
• (Oct. 30, 2019) Talk: Koichi Murase, Modification to fluctuation-dissipation relation and fluctuation-theorem, Workshop "New Development of Hydrodynamics and its applications in Heavy-ion Collisions", Shanghai, China
• (Sep. 18, 2019) Talk (Japanese): Azumi Sakai, Tetsufumi Hirano, Hirotsugu Fujii, Koichi Murase, 18aS22-3 「1次元膨張系における臨界揺らぎの時空発展」, JPS Autumn Meeting 2019, Yamagata University, Japan
• (Aug. 28, 2019) Seminar (Japanese): Koichi Murase, "高エネルギー重イオン衝突反応と流体力学的ゆらぎ (High-energy heavy-ion collisions and hydrodynamic fluctuations)", H-Ken, Nagoya University, Nagoya
• (Aug. 19, 2019) Invited Talk (Japanese): Koichi Murase, "流体・フロー (Hydrodynamics and Flow)", RIKEN Wako Campus, Saitama
• (Jul. 31, 2019) Invited Talk (Japanese): Koichi Murase, "原子核衝突における相対論的粘性流体 (Relativistic viscous hydrodynamical calculations for nuclear collisions)", Kyoto University, Kyoto
• (Jun. 25, 2019) Talk: Koichi Murase, "Hydrodynamic fluctuations and fluctuation theorem in heavy-ion collisions", XQCD 2019, University of Tsukuba, Tokyo
• (Jun. 22, 2019) Invited Talk (Japanese): Koichi Murase, "Dynamical description of hydrodynamic fluctuations in high-energy nuclear collisions, 36th Heavy Ion Cafe, Sophia University, Tokyo
• (Jun. 03, 2019) Seminar (Japanese): Koichi Murase, "高エネルギー重イオン衝突反応における流体力学的ゆらぎの物理 (Physics of hydrodynamic fluctuations in high-energy heavy-ion collisions)", 原子核理論研究室, Osaka University, Osaka
• (May. 21, 2019) Seminar: Koichi Murase, "Hydrodynamic fluctuations in high-energy nuclear collisions", CHEP, PKU, Beijing, China
• (May. 11, 2019) Invited Talk: Koichi Murase, "Hydrodynamic fluctuations in integrated dynamical model", Workshop on Partonic and Hadronic Transport Approaches for Relativistic Heavy Ion Collisions, Dalian, China
• (Apr. 26, 2019) Paper: Koichi Murase, [1904.11217] Causal hydrodynamic fluctuations in non-static and inhomogeneous backgrounds

OSS Activities

Softwares

See also Repositories on GitHub.

Useful

• Bash configuration ble.sh ★★★
  • Syntax highlighting in Bash interactive sessions (like fish and zsh-syntax-highlighting)
  • Enhanced vi/vim editing mode
• Chrome Extension akinomyoga.msdn-english-button
  • Show links for Japanese MSDN pages to the corresponding English pages
• Chrome Extension agh.addon.aghtex4chrome
  • Render TeX files in Chrome
  • Render mathematical formulae in Gmail
• JavaScript Library agh
  • TeX interpreter written in JavaScript
  • PostScript interpreter written in JavaScript
  • etc.
• PHP Wiki Engine lwiki
  • Simple & easy to setup (but I haven't yet written README...)

Samples & Demonstration

• Cygwin Library cyglocale_patcher
  • Fix a bug of locales in cygwin1.dll (v2.7.0)
  • Sample of hot patching (API hooking)
• AWK script mwg_pp/ev3v2.awk
  • Interpreter of a language like JavaScript/ECMAScript written in GNU awk script
  • Hand-written LR parser

Bug reports & fixes

See also the GitHub profile. The following list is a summary of activities not showing up in the GitHub profile.

• (Jun. 6, 2026) Report Cygwin/cygwin1.dll Cygwin-3.6.9: pcon: CPR responses are broken when a non-Cygwin executable starts
• (Jul. 7, 2024) Fix Bash [PATCH] fix `shopt -u force_fignore' affecting unrelated parts
• (Jun. 1, 2024) Fix Bash [PATCH] fix uneccesary copy of function bodies for BASH_SOURCE
• (Apr. 28, 2024) Report Bash 5.3-alpha: the `jobs' builtin prints foreground dead jobs with function
• (Apr. 28, 2024) Report Bash 5.3-alpha: value substitutions remove unrelated REPLY when its REPLY is
• (Feb. 24, 2024) Discussion Bash exec redirection is undone if fd (>9) has O_CLOEXEC
• (Sep. 15, 2023) Report Bash 5.3: job error caused by funsub + bind + loadable builtin
• (Feb. 3, 2022) Report Cygwin/cygwin1.dll In Cygwin console (not Mintty), escape sequences DL/IL at the last line misbehave
• (Sep. 24, 2022) Fix Bash [PATCH] 4.3..devel: Fix printf %d "'X" affected by intermediate mbstate_
• (Sep. 2, 2022) Fix Bash [PATCH] Calling `trap xxx INT' in completion functions of `complete -F'
• (Jul. 18, 2022) Fix Bash [PATCH] Fix leaked internal escapes of patsub_replacement ${var/$pat/"&"
• (Jul. 18, 2022) Fix Bash [PATCH] Fix foreground dead jobs in trap handlers reported like backgrou
• (Mar. 13, 2022) Fix Bash [PATCH] Fix escaping of \034 (^\) in paths for \w, \W, and \s
• (Oct. 6, 2021) Fix Bash [PATCH] 4.0..devel: fix a problem that unset 'a[`echo 0`]' causes "bad a
• (Oct. 5, 2021) Fix Bash [PATCH] devel: fix segfault by unset 'assoc[${x[0]}]'
• (Oct. 5, 2021) Discussion Bash devel: Questions about quoting in the new replacement ${var/pat/&}
• (Sep. 22, 2021) Fix Bash [PATCH] fix the termcap string for _rl_term_kP
• (Jun. 27, 2021) Fix Bash [PATCH] quote command and function names in `complete -p' - noreply?
• (Jun. 27, 2021) Fix Bash [PATCH] Fix READLINE_ARGUMENT with "M-1 M-2" and with `vi-arg-digit'
• (Jun. 27, 2021) Fix Bash [PATCH] fix super-linear complexity of ${v^} and ${v//A}
• (May. 2, 2021) Discussion Bash Why does "mapfile -d delim" (delim != '\n') use unbuffered read?
• (Apr. 9, 2021) Discussion Bash Feature request: Empty associative-array keys
• (Feb. 8, 2021) Fix Bash [PATCH] Fix blocking read timeouts at a small probability
• (Aug. 31, 2020) Fix Bash [PATCH] Fix segfault with self-modifying array PROMPT_COMMAND
• (Aug. 28, 2020) Fix Bash [PATCH] Bash 5.0+: Fix a problem that interactive sessions close with `e
• (Aug. 23, 2020) Discussion Bash How to use PROMPT_COMMAND(S) without breaking other scripts
• (Apr. 20 2020) Patch Bash [PATCH] Implement rehashing for associative arrays (Re: speeding up hash
• (Apr. 17, 2020) Report/Discussion Bash/POSIX [PATCH] Exit status by no-argument `return' for function calls in trap h XCU 2.14: Exit status by no-argument `return' in shell trap handlers
• (Feb. 8, 2020) Report Cygwin/cygwin1.dll Koichi Murase - Cygwin-3.1.3: Terminal contents are overwritten by less graphical ones o
• (Feb. 8, 2020) Question Cygwin/cygwin1.dll Koichi Murase - Question on pseudo console and legacy console
• (Jan. 30, 2020) Report GNU Screen GNU Screen - Bugs: bug #57697, 4.99.0: CPU usage always 100%... [Savannah]
• (Jan. 24, 2020) Report Cygwin/cygwin1.dll Koichi Murase - Cygwin-3.1.3: read(2) from /dev/consN returns unexpected EOF after selec [fixed by Takashi Yano - [PATCH] Cygwin: console: Share readahead buffer within the same process.]
• (Jan. 23, 2020) Report Cygwin/cygwin1.dll Koichi Murase - Cygwin 3.3.0: The programs compiled with "-mwindows" cannot read more th [fixed by Takashi Yano - [PATCH] Cygwin: pty: Remove close() call just before reopening slave.]
• (Jan. 22, 2020) Fix Bash [PATCH] Resolve inconsisteny of keyseq representation of \C-\\ (0x5c)
• (Jan. 20, 2020) Report Cygwin/cygwin1.dll Koichi Murase - Cygwin 3.1.2: Every call of exec(2) in the session starts to create a co [fixed by Takashi Yano - [PATCH] Cygwin: pty: Fix reopening slave in push_to_pcon_screenbuffer().]
• (Jan. 8, 2020) Report FreeBSD/libc 243195 – [libc] setlocale(LC_COLLATE, "...") causes segmentation fault after certain number of calls [fixed by ⚙ D23109 libc: Fix a few bugs in the xlocale collation code.]
• (Dec. 19, 2019) Fix Bash [PATCH] Fix a problem `rl_bind_key' cannot create shadow binding for `C- [reply]
• (Dec. 19, 2019) Fix Bash [PATCH] Fix a problem that shadow `bind -x' is not removed from `bind -X
• (Dec. 19, 2019) Fix Bash [PATCH] Fix a problem that shadow `bind -x' does not work [reply]
• (Jul. 22, 2019) Report/Fix GNU Awk [bug-gawk] Error messages on negative arguments for `and(a, b)/or(a, b)/
• (Feb. 11, 2019) Report/Fix Bash [PATCH] Support `bind -x' for different keymaps Re: bind -X shows inactive bindings (bindings removed using bind -r)
• (Feb. 11, 2019) Fix Bash [PATCH] Fix a bug that `bind -x '"metachar":command'' fails when rl-vari
• (Feb. 11, 2019) Fix Bash [PATCH] Switch vi-insert TAB binding only for the default binding
• (Feb. 11, 2019) Fix Bash [PATCH] Fix a broken unwind frame on `builtin bind --help'
• (May. 5, 2018) Fix Bash [PATCH] `bind -x' inside `bind -x' bindings causes execution of random s
• (Apr. 9, 2018) Fix Bash [PATCH] READLINE_POINT with multibyte locales
• (Mar. 21, 2018) Fix Bash [PATCH] fix a bug that bind -x '"\C-@": unix-command' does not work
• (Mar. 19, 2018) Report Bash [PATCH: bash-5.0.0(2)-alpha] fix a bug that "bind -r" sometimes causes a
• (Aug. 9, 2017) Report g++, clang++, msvc c++ - Correct behavior of built-in operator candidates of overload resolution in the operator expression context - Stack Overflow [ Reports based on this: gcc 81789, llvm 34138, visualstudio 92207 ]
• (Mar. 12, 2017) Fix cygwin1.dll Koichi MURASE - [PATCH, newlib/libc/locale] Fix broken '_duplocale_r' which called '__lo
• (Dec. 17, 2016) Report g++ 78840 - [5/6/7 Regression] ICE with const variables in templates implicitly captured by nested lambda expressions
• (Nov. 7, 2016) Fix Bash In ((0? var: 0)), expressions stored in var are evaluated. [Official patch: bash44-008]
• (Nov. 6, 2016) Fix Bash "builtin printf '\uFF8E'" generates broken surrogate pairs in Cygwin
• (Apr. 25, 2015) Report g++ 65885 - lambda expressions in templates fail to capture `const int' variables