「幾何学的群論の深化と展開」 基盤研究(S)
研究課題/領域番号15H05739
研究代表者: 藤原 耕二 京都大学・理学研究科・教授 (60229078)
研究分担者：山口 孝男 京都大学・理学研究科・教授 (00182444); 小沢 登高 京都大学・数理解析研究所・教授 (60323466); 塩谷 隆 東北大学・理学研究科・教授 (90235507).
研究期間 (年度) 2015-05-29 -- 2020-03-31
研究進捗評価 H30:A

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特定研究員：

• H27: 蒲谷祐一 (H28-, 北見工大・准教授）
• H28: 武石拓也　（H29-, 京大数理研・研究員）、蓮井翔（H29-, 大阪府立大・教育拠点形成教員）
• H29: 吉田建一
• H30:吉田建一（H31-, 埼玉大・連携研究員), 湯淺 亘（H31-, 学振PD)
• H31/R1:福本佳奏(H32-, 京大・教務補佐員）
• R3（繰越）：藤岡禎司

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Publication

• Bestvina, Mladen; Bromberg, Ken; Fujiwara, Koji; Sisto, Alessandro Acylindrical actions on projection complexes. Enseign. Math. 65 (2020), no. 1-2, 1-32.
• Fujiwara, Koji; Kabaya, Yuichi Computing Kazhdan constants by semidefinite programming. Exp. Math. 28 (2019), no. 3, 301-312.
• Koji Fujiwara, Constructing group actions on quasi-trees. Proceedings of the International Congress of Mathematicians, Rio de Janeiro 2018. Vol. II. Invited lectures, 1087-1114, World Sci. Publ., Hackensack, NJ, 2018.
• Fujiwara, Koji; Kapovich, Michael. On quasihomomorphisms with noncommutative targets. Geom. Funct. Anal. 26 (2016), no. 2, 478--519.
• Bestvina, Mladen; Bromberg, Ken; Fujiwara, Koji. Stable commutator length on mapping class groups. Ann. Inst. Fourier 66 (2016), no. 3, 871--898.
• Bestvina, Mladen; Bromberg, Ken; Fujiwara, Koji. Bounded cohomology with coefficients in uniformly convex Banach spaces. Comment. Math. Helv. 91 (2016), no. 2, 203--218. Bl Article
• Bestvina, Mladen; Bromberg, Ken; Fujiwara, Koji. Constructing group actions on quasi-trees and applications to mapping class groups. Publ. Math. Inst. Hautes ÉEudes Sci. 122 (2015), 11-64.
• Calegari, Danny; Fujiwara, Koji. Counting subgraphs in hyperbolic graphs with symmetry. J. Math. Soc. Japan 67 (2015), no. 3, 1213--1226.
• Fujiwara, Koji. Asymptotically isometric metrics on relatively hyperbolic groups and marked length spectrum. J. Topol. Anal. 7 (2015), no. 2, 345--359.
• Fujiwara, Koji. Subgroups generated by two pseudo-Anosov elements in a mapping class group. II. Uniform bound on exponents. Trans. Amer. Math. Soc. 367 (2015), no. 6, 4377--4405.

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Talks

• Fujiwara, 2015. Cornell Topology Festival. USA.
• Fujiwara, 2015. 日本数学会秋季総合分科会、総合講演（秋季賞受賞講演）、京都産業大学
• Fujiwara, 2016. Introductory Workshop: Geometric Group Theory. MSRI. Berkeley. USA.
• Fujiwara, 2017. Colloquium. U of Warwick. UK
• Fujiwara, 2018. International Congress of Mathematicians, Rio de Janeiro 2018. Vol. II. Invited lectures(Topology section).
• 藤原耕二　2019.非ユークリッド幾何の世界。玉城嘉十郎教授記念公開学術講演会. 「幾何の世界と対称性」。京都大学理学研究科

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Conferences

• 「離散群の幾何解析」 at RIMS. 2016-05-30〜2016-06-03, organized by Fujiwara and Ozawa