FUKUSHIMA Ryoki

Affiliation

Institute of Pure and Applied Sciences

Official title

Professor

ORCID

0000-0002-7582-6793

URL

http://www.math.tsukuba.ac.jp/~ryoki/

Research fields

Basic analysis

Research keywords

Limit theorem
Analysis
Homogenization
Percolation
Large deviation
Random media
Disordered media
Stochastic process
Probability theory
Mathematics

Research projects

Research on first passage percolation in disordered media	2025 -- 2029	福島 竜輝	Japan Society for the Promotion of Science/Grant-in-Aid for Scientific Research(B)	11,960,000Yen
不規則媒質中の最速浸透問題の研究 研究課題	2025-04 -- 2030-03	福島竜輝	日本学術振興会/基盤研究(B)	11,960,000Yen
ランダム媒質中の確率過程の定量的研究	2021-04 -- 2024-03		日本学術振興会/基盤研究(C)	2,340,000Yen
Stochastic analysis and applications	2012-01 -- 2014-01	竹田雅好	日本学術振興会/二国間交流事業（日独）	400,000Yen
ランダム媒質における均質化と揺らぎの研究 （平成29年度分）	2017-01 -- 2018-01		Japan Society of for the Promotion of Science/基盤研究(C)	1,430,000Yen
ランダム媒質における均質化と揺らぎの研究 （平成28年度分）	2016-01 -- 2017-01		Japan Society of for the Promotion of Science/基盤研究(C)	1,300,000Yen
ランダム媒質中の確率過程 （平成27年度分）	2015-01 -- 2016-01		Japan Society of for the Promotion of Science/若手研究（Ｂ）	780,000Yen
ランダム媒質中の確率過程	2012-01 -- 2016-01		Japan Society of for the Promotion of Science/若手研究(B)	3,120,000Yen
ランダム媒質中の確率過程 （平成26年度分）	2014-01 -- 2015-01		Japan Society of for the Promotion of Science/若手研究（Ｂ）	780,000Yen
ランダム媒質中の確率過程	2012-01 -- 2015-01		Japan Society of for the Promotion of Science/若手研究（Ｂ）	780,000Yen
more...

Degree

2008-07	博士（理学）	京都大学
2007-03	修士（理学）	京都大学

Licenses and qualifications

2020-11	普通自動車免許

Academic societies

2008-04 -- (current)	The Mathematical Society of Japan

Honors & Awards

2024-9	日本数学会解析学賞	ランダム媒質から誘導される複雑な系上の統計力学模型の解析
2016-01	Young Scientists' Prize for Science and Technology by MEXT
2009-01	Inoue Research Award for Young Scientists
2009-01	Takebe Prizes

Articles

• Extremal regime for one-dimensional Mott variable-range hopping
  福島 竜輝; David Croydon; Stefan Junk
  Annales Henri Lebesgue/6/pp.1169-1211, 2023-11
• Anomalous scaling regime for one-dimensional Mott variable-range hopping
  福島 竜輝; David Croydon; Stefan Junk
  The Annals of Applied Probability/33(5)/pp.4044-4090, 2023-10
• Moment characterization of the weak disorder phase for directed polymers in a class of unbounded environments
  Fukushima Ryoki; Junk Stefan
  ELECTRONIC COMMUNICATIONS IN PROBABILITY/28, 2023-04-01
• The period group of a characteristic function
  Fukushima Ryoki; Nakashima Makoto; Yoshida Nobuo
  REAL ANALYSIS EXCHANGE/47(2)/pp.323-332, 2023-02
• Number of paths in oriented percolation as zero temperature limit of directed polymer
  福島 竜輝; Junk Stefan
  PROBABILITY THEORY AND RELATED FIELDS/183(3-4)/pp.1119-1151, 2022-05
• 「確率論とポテンシャル」
  福島 竜輝
  月刊誌「数理科学」, 2022-03
• Note on the maximal jump size in a continuum model of directed first passage percolation
  福島 竜輝
  Advanced Studies in Pure Mathematics/87/pp.213-226, 2022-01
• On large deviation rate functions for a continuous-time directed polymer in weak disorder
  福島 竜輝; Junk Stefan
  Electron. Commun. Probab./26/pp.1-10, 2021-03
• Distribution of the random walk conditioned on survival among quenched Bernoulli obstacles
  福島 竜輝; Ding Jian; Sun Rongfeng; Xu Changji
  Ann. Probab./49/pp.206-243, 2021-01
• Quenched tail estimate for the random walk in random scenery and in random layered conductance II
  Deuschel Jean-Dominique; Fukushima Ryoki
  ELECTRONIC JOURNAL OF PROBABILITY/25(75), 2020-06
• Geometry of the random walk range conditioned on survival among Bernoulli obstacles
  Jian Ding Ryoki Fukushima Rongfeng Sun Changji Xu
  Probability Theory and Related Fields/177/pp.91-145, 2020-06
• Biased Random Walk Conditioned on Survival Among Bernoulli Obstacles: Subcritical Phase
  Jian Ding Ryoki Fukushima Rongfeng Sun Changji Xu
  Communications in Mathematical Physics/376/pp.2161-2195, 2020-06
• New high-dimensional examples of ballistic random walks in random environment
  Ryoki Fukushima Alejandro Ramirez
  RIMS Kokyuroku Bessatsu, B79: Stochastic Analysis on Large Scale Interacting Systems/pp.109-122, 2020-04
• Zero temperature limit for the Brownian directed polymer among Poissonian disasters
  Ryoki Fukushima Stefan Junk
  The Annals of Applied Probability/29/pp.3821-3860, 2019-12
• Quenched tail estimate for the random walk in random scenery and in random layered conductance
  Jean-DominiqueDeuschel Ryoki Fukushima
  Stochastic Process. Appl./129(1)/pp.102-128, 2019-01
• Slowdown estimates for one-dimensional random walks in random environment with holding times
  Amir Dembo; Ryoki Fukushima; Naoki Kubota
  Electron. Commun. Probab./23(89)/pp.1-12, 2018-11
• Eigenvlaue fluctuations for lattice Anderson Hamiltonians: unbounded potentials
  Marek Biskup Ryoki Fukushima Wolfgang Koenig
  Interdiscip. Inform. Sci./24(1)/pp.59-76, 2018-06
• Eigenvalue fluctuations for lattice Anderson Hamiltonians
  Marek Biskup Ryoki Fukushima Wolfgang Koenig
  SIAM J. Math. Anal./48(4)/pp.2674-2700, 2016-01
• Limiting results for the free energy of directed polymers in random environment with unbounded jumps
  Francis Comets Ryoki Fukushima Shuta Nakajima Nobuo Yo...
  J. Stat. Phys./161(3)/pp.577-597, 2015-01
• Quenched large deviations for multidimensional random walk in random environment with holding times
  Ryoki Fukushima Naoki Kubota
  J. Theoret. Probab./27(4)/pp.1140-1166, 2014-01
• Annealed Brownian motion in a heavy tailed Poissonian potential
  Ryoki Fukushima
  Ann. Probab./41(5)/pp.3462-3493, 2013-01
• On exponential growth for a certain class of linear systems
  Ryoki Fukushima Nobuo Yoshida
  ALEA Lat. Am. J. Probab. Math. Stat./9(2)/pp.323-336, 2012-01
• Second order asymptotics for Brownian motion in a heavy tailed Poissonian potential
  Ryoki Fukushima
  Markov Process. Related Fields/17(3)/pp.447-482, 2011-10
• Moment asymptotics for the parabolic Anderson problem with a perturbed lattice potential
  Ryoki Fukushima Naomasa Ueki
  J. Funct. Anal./260(3)/pp.724-744, 2011-02
• Classical and quantum behavior of the integrated density of states for a randomly perturbed lattice
  Ryoki Fukushima Naomasa Ueki
  Ann. Henri Poincaré/11(6)/pp.1053-1083, 2010-11
• more...

Books

• 授業では教えてくれない微積分学
  福島 竜輝
  森北出版, 2024-11
• 第Ⅱ部第11.2節
  福島 竜輝
  確率論ハンドブック/丸善出版, 2012-07
• 「ランダム作用素」
  福島 竜輝
  月刊誌「数理科学」/サイエンス社, 2016-06

Conference, etc.

• Leading term of maximal edge traversal time in first passage percolation with Weibull distribution
  FUKUSHIMA Ryoki
  Third China-Japan-Korea Joint Probability Workshop/2025-05-08
• Leading term of maximal edge traversal time in first passage percolation with Weibull distribution
  FUKUSHIMA Ryoki
  NYUSH-Peking-Westlake probability conference/2025-04-10
• Leading term of maximal edge traversal time in first passage percolation with Weibull distribution
  FUKUSHIMA Ryoki
  Tsinghua-Tokyo Workshop on PDEs and Probability/2025-03-22
• ランダムな障害物を避けるランダムウォーク
  福島 竜輝
  日本数学会2025年度年会，解析学賞受賞特別講演/2025-03-18
• Number of paths in oriented percolation as zero temperature limit of directed polymer
  福島 竜輝
  LA Probability Forum/2025-03-06
• Sub-diffusive scaling regime for one-dimensional Mott Variable-Range Hopping
  福島 竜輝
  Random Operators and Related Topics 2024/2024-11-16
• Maximal edge traversal time in first passage percolation
  福島 竜輝
  Recent development in KPZ universality/2024-09-24
• Sub-diffusive scaling regime for one-dimensional Mott variable range hopping
  FUKUSHIMA Ryoki
  Homogenization in PDE and stochastic processes/2024-08-20
• Distribution of the random walk conditioned on survival among quenched Bernoulli obstacles
  福島 竜輝
  Random walks, scaling limits and criticality/2024-05-20
• Subdiffusive scaling regime for one-dimensional Mott Variable-Range Hopping
  福島 竜輝
  Interacting particle systems and SPDEs, China-Japan Probability Workshop at BIMSA and YMSC/2024-03-24
• Number of paths in oriented percolation as Ryoki Fukushima zero temperature limit of directed polymer
  福島 竜輝
  Random Interacting Systems, Scaling Limits, and Universality/2023-12-04
• Distribution of the random walk conditioned on survival among quenched Bernoulli obstacles
  福島 竜輝
  Random Operators and Related Topics/2023-10-14
• Concentration inequalities in random media
  福島 竜輝
  Mathematics of Random Systems Summer School/2023-09-11--2023-09-15
• Recent results on RW among random obstacles
  福島 竜輝
  Stochastic Processes and Related Fields/2023-09-04
• Distribution of the random walk conditioned on survival among quenched Bernoulli obstacles
  福島 竜輝
  Workshop on Probabilistic Methods in Statistical Mechanics of Random Media and Random Fields 2023/2023-01-09--2023-01-13
• Number of paths in oriented percolation as zero temperature limit of directed polymer
  福島 竜輝
  Open German-Japanese conference on stochastic analysis and applications/2022-09-19--2022-09-23
• Zero temperature limits of directed polymers in random environment
  Fukushima Ryoki
  Workshop on Probabilistic Methods in Statistical Mechanics of Random Media and Random Fields 2022/2022-01-11--2022-01-14
• Zero temperature limits of directed polymers in random environment
  福島 竜輝
  Workshop on Probabilistic Methods in Statistical Mechanics of Random Media and Random Fields 2022/2022-01-11--2022-01-14
• Biased random walk conditioned on survival among Bernoulli obstacles
  福島 竜輝
  Stochastic Analysis on Large Scale Interacting Systems/2021-12-07--2021-12-09
• Number of paths in oriented percolation as zero temperature limit of directed polymer
  福島 竜輝
  The 10th International Conference on Stochastic Analysis and its Applications/2021-09-06--2021-09-10
• Biased random walk conditioned on survival among Bernoulli obstacles: subcritical phase
  福島 竜輝
  日本数学会年会/2021-03-15
• Geometry of the random walk range conditioned on survival among Bernoulli obstacles
  福島 竜輝
  日本数学会年会/2021-03-15
• Quenched tail estimate for the random walk in random scenery II
  福島 竜輝
  日本数学会年会/2021-03-15
• Biased random walk conditioned on survival among Bernoulli obstacles: sub-critical phase
  福島竜輝
  Spectra of Random Operators and Related Topics/2020-01-01
• Random walk conditioned on survival among Bernoulli obstacles
  福島竜輝
  台湾数学会年会/2019-12-01
• more...

Teaching

2025-05 -- 2025-08	Exercises in Calculus S	University of Tsukuba.
2025-10 -- 2025-12	Exercises in Calculus F	University of Tsukuba.
2025-10 -- 2026-02	Research Proposal in Pure and Applied Sciences	University of Tsukuba.
2025-04 -- 2025-08	Research Proposal in Pure and Applied Sciences	University of Tsukuba.
2025-10 -- 2026-02	Seminar on Mathematics	University of Tsukuba.
2025-04 -- 2025-08	Seminar on Mathematics	University of Tsukuba.
2025-10 -- 2026-02	Internship in Mathematics IV	University of Tsukuba.
2025-04 -- 2025-08	Internship in Mathematics IV	University of Tsukuba.
2025-10 -- 2026-02	Internship in Mathematics III	University of Tsukuba.
2025-04 -- 2025-08	Internship in Mathematics III	University of Tsukuba.
more...

Other educational activities

2022-08 -- 2022-08	筑波大学数学類体験学習	筑波大学数学類
2022-10 -- 2022-10	早稲田大学 SGU 特別講義「ランダム媒質中の確率過程」	早稲田大学

Professional activities

2020-01 -- 2023-12	Bernoulli Society for Mathematical Statistics and Probability	East Asian and Pacific Regional Committee
2020-01 -- 2025-12	Bernoulli Society for Mathematical Statistics and Probability	Committee for Conferences on Stochastic Processes
2020-03 -- 2022-02	The Mathematical Society of Japan	統計数学分科会運営委員

University Management

2024-04 -- 2025-03	ダイバーシティ・アクセシビリティ担当教員
2020-04 -- 2021-03	障害学生支援に係るダイバーシティ・アクセシビリティ担当教員

(Last updated: 2025-07-23)