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Structures of symplectic derivation Lie algebras and characteristic classes of moduli spaces

Research Project

Project/Area Number 15H03618
Research Category

Grant-in-Aid for Scientific Research (B)

Allocation TypeSingle-year Grants
Section一般
Research Field Geometry
Research InstitutionThe University of Tokyo

Principal Investigator

Sakasai Takuya  東京大学, 大学院数理科学研究科, 准教授 (60451902)

Co-Investigator(Kenkyū-buntansha) 森田 茂之  東京大学, 大学院数理科学研究科, 名誉教授 (70011674)
鈴木 正明  明治大学, 総合数理学部, 専任教授 (70431616)
Project Period (FY) 2015-04-01 – 2019-03-31
Project Status Completed (Fiscal Year 2018)
Budget Amount *help
¥10,790,000 (Direct Cost: ¥8,300,000、Indirect Cost: ¥2,490,000)
Fiscal Year 2018: ¥2,340,000 (Direct Cost: ¥1,800,000、Indirect Cost: ¥540,000)
Fiscal Year 2017: ¥2,990,000 (Direct Cost: ¥2,300,000、Indirect Cost: ¥690,000)
Fiscal Year 2016: ¥2,470,000 (Direct Cost: ¥1,900,000、Indirect Cost: ¥570,000)
Fiscal Year 2015: ¥2,990,000 (Direct Cost: ¥2,300,000、Indirect Cost: ¥690,000)
Keywordsトポロジー / モジュライ空間 / グラフホモロジー / Johnson 準同型 / シンプレクティック微分 / 特性類 / 幾何学
Outline of Final Research Achievements

As joint works of the members of our research team, we obtained the following results concerning the cohomology groups of moduli spaces of Riemann surfaces and graphs:

(1) We gave another proof of Bartholdi's result on the 11th rational homology group of the moduli space of graphs of rank 7. (2) We determined the structure of the Lie algebra of Johnson images up to degree 7. (3) We compared certain two filtrations of the Torelli group up to degree 6. This result provides a new insight on the finite type invariants of homology 3-spheres. Also, we determined the rational abelianization of the Johnson kernel. (4) In a joint work with Gwenael Massuyeau, we proved that the rational abelianization of the homology cobordism group of surfaces is non-trivial.

Academic Significance and Societal Importance of the Research Achievements

リーマン面のモジュライ空間は100年以上の研究の歴史を持つ数学的対象であり,この空間の構造を調べることが新たな数学を生み出す原動力となってきた.グラフのモジュライ空間もまた,類似の空間としてその重要性が注目されている.それらの空間の不変量である特性類を見つけることは,それらを測るための新たな「尺度」を作ることであり,その応用は数学にとどまらず数理物理など広範囲にわたると期待される.本研究では,いくつかの特性類の直接計算や,種々の特性類の関係性を統一的に記述するための方法を与えた.それらの応用として,3次元多様体の新たな不変量の構成や,既存の不変量に関する新たな知見を得た.

Report

(5 results)
  • 2018 Annual Research Report   Final Research Report ( PDF )
  • 2017 Annual Research Report
  • 2016 Annual Research Report
  • 2015 Annual Research Report
  • Research Products

    (67 results)

All 2019 2018 2017 2016 2015 Other

All Int'l Joint Research (4 results) Journal Article (8 results) (of which Int'l Joint Research: 1 results,  Peer Reviewed: 8 results,  Acknowledgement Compliant: 2 results,  Open Access: 1 results) Presentation (49 results) (of which Int'l Joint Research: 21 results,  Invited: 33 results) Remarks (2 results) Funded Workshop (4 results)

  • [Int'l Joint Research] Universite de Bourgogne(フランス)

    • Related Report
      2018 Annual Research Report
  • [Int'l Joint Research] Universite de Bourgogne(France)

    • Related Report
      2017 Annual Research Report
  • [Int'l Joint Research] IRMA (University of Strasbourg)(France)

    • Related Report
      2016 Annual Research Report
  • [Int'l Joint Research] IRMA (University of Strasbourg)(France)

    • Related Report
      2015 Annual Research Report
  • [Journal Article] 曲面の写像類群と自由群の外部自己同型群のコホモロジーに関するこれまでの歩みと最近の進展2018

    • Author(s)
      逆井卓也
    • Journal Title

      数学(日本数学会)

      Volume: 70 Pages: 225-254

    • NAID

      130007880390

    • Related Report
      2018 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Morita's trace maps on the group of homology cobordisms2018

    • Author(s)
      Gwenael Massuyeau, Takuya Sakasai
    • Journal Title

      Journal of Topology and Analysis

      Volume: 印刷中

    • Related Report
      2018 Annual Research Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] Symmetry of symplectic derivation Lie algebras of free Lie algebras.2017

    • Author(s)
      Shigeyuki Morita, Takuya Sakasai and Masaaki Suzuki
    • Journal Title

      RIMS Kokyuroku Bessatsu

      Volume: 66 Pages: 185-193

    • Related Report
      2017 Annual Research Report
    • Peer Reviewed
  • [Journal Article] An abelian quotient of the symplectic derivation Lie algebra of the free Lie algebra2017

    • Author(s)
      Shigeyuki Morita, Takuya Sakasai and Masaaki Suzuki
    • Journal Title

      Experimental Mathematics

      Volume: 印刷中 Issue: 3 Pages: 302-315

    • DOI

      10.1080/10586458.2016.1266975

    • Related Report
      2016 Annual Research Report
    • Peer Reviewed / Acknowledgement Compliant
  • [Journal Article] Symmetry of symplectic derivation Lie algebras of free Lie algebras2017

    • Author(s)
      Shigeyuki Morita, Takuya Sakasai and Masaaki Suzuki
    • Journal Title

      RIMS Kokyuroku Bessatsu

      Volume: 印刷中

    • Related Report
      2016 Annual Research Report
    • Peer Reviewed / Acknowledgement Compliant
  • [Journal Article] Structure of symplectic invariant Lie subalgebras of symplectic derivation Lie algebras2015

    • Author(s)
      Shigeyuki Morita, Takuya Sakasai and Masaaki Suzuki
    • Journal Title

      Advances in Mathematics

      Volume: 282 Pages: 291-334

    • DOI

      10.1016/j.aim.2015.06.017

    • Related Report
      2015 Annual Research Report
    • Peer Reviewed / Open Access
  • [Journal Article] The Magnus representation and homology cobordism groups of homology cylinders2015

    • Author(s)
      Takuya Sakasai
    • Journal Title

      Journal of Mathematical Sciences, the University of Tokyo

      Volume: 22 Pages: 741-770

    • NAID

      120005819510

    • Related Report
      2015 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Computations in formal symplectic geometry and characteristic classes of moduli spaces2015

    • Author(s)
      Shigeyuki Morita, Takuya Sakasai and Masaaki Suzuki
    • Journal Title

      Quantum Topology

      Volume: 6 Issue: 1 Pages: 139-182

    • DOI

      10.4171/qt/61

    • Related Report
      2015 Annual Research Report
    • Peer Reviewed
  • [Presentation] Two filtrations of the Torelli group2019

    • Author(s)
      Masaaki Suzuki
    • Organizer
      East Asian Conference on Geometric Topology 2019
    • Related Report
      2018 Annual Research Report
    • Int'l Joint Research / Invited
  • [Presentation] Topological studies of moduli spaces of Riemann surfaces and their generalizations2019

    • Author(s)
      Takuya Sakasai
    • Organizer
      Quantum Math
    • Related Report
      2018 Annual Research Report
    • Invited
  • [Presentation] グラフホモロジー: 定義と応用2019

    • Author(s)
      逆井卓也
    • Organizer
      Encounter with Mathematics (第73回)
    • Related Report
      2018 Annual Research Report
    • Invited
  • [Presentation] グラフホモロジーとモジュライ空間のホモロジー群2018

    • Author(s)
      逆井卓也
    • Organizer
      種々の幾何学的構造と基本群に現れる様々な特性類とその不変量への応用
    • Related Report
      2018 Annual Research Report
    • Invited
  • [Presentation] Computations on Johnson homomorphisms2018

    • Author(s)
      Masaaki Suzuki
    • Organizer
      New Trends in Teichmuller Theory and Mapping Class Groups
    • Related Report
      2018 Annual Research Report
    • Int'l Joint Research / Invited
  • [Presentation] Computations on Johnson homomorphisms2018

    • Author(s)
      Takuya Sakasai
    • Organizer
      Cohomological study of mapping class groups and related topics
    • Related Report
      2018 Annual Research Report
    • Int'l Joint Research
  • [Presentation] Torelli group, Johnson kernel and invariants of homology 3-spheres2018

    • Author(s)
      逆井卓也
    • Organizer
      トポロジー火曜セミナー
    • Related Report
      2018 Annual Research Report
  • [Presentation] Two filtrations of the Torelli group2018

    • Author(s)
      鈴木正明
    • Organizer
      トポロジーとコンピュータ 2018
    • Related Report
      2018 Annual Research Report
  • [Presentation] Motivic Lie algebra and cohomology of moduli spaces of graphs and curves2018

    • Author(s)
      Shigeyuki Morita
    • Organizer
      Topology and Geometry of Low-dimensional Manifolds
    • Related Report
      2018 Annual Research Report
    • Int'l Joint Research / Invited
  • [Presentation] (1) The mapping class group action in shear coordinates, (2) Mapping class group actions on moduli spaces of 3d gravity2018

    • Author(s)
      逆井卓也
    • Organizer
      モジュライ空間のシンプレクティック幾何, 東京大学
    • Related Report
      2017 Annual Research Report
  • [Presentation] Epimorphisms between knot groups - crossing number, genus2018

    • Author(s)
      Masaaki Suzuki
    • Organizer
      The 13th East Asian School of Knots and Related Topics, KAIST (韓国)
    • Related Report
      2017 Annual Research Report
    • Int'l Joint Research / Invited
  • [Presentation] (Non-)triviality of characteristic classes on flat bundles2018

    • Author(s)
      Shigeyuki Morita
    • Organizer
      BΓ School III, 中央大学
    • Related Report
      2017 Annual Research Report
    • Int'l Joint Research / Invited
  • [Presentation] Homologically fibered knots and closed 3-manifolds2017

    • Author(s)
      逆井卓也
    • Organizer
      筑波大学トポロジーセミナー
    • Place of Presentation
      筑波大学 (茨城県つくば市)
    • Year and Date
      2017-02-21
    • Related Report
      2016 Annual Research Report
    • Invited
  • [Presentation] Casson invariant and structure of the mapping class group2017

    • Author(s)
      森田茂之
    • Organizer
      Casson 不変量に関わる3次元多様体の不変量
    • Place of Presentation
      京都大学数理解析研究所 (京都府京都市)
    • Year and Date
      2017-01-25
    • Related Report
      2016 Annual Research Report
    • Invited
  • [Presentation] Cohomology of the moduli space of graphs and groups of homology cobordisms of surfaces2017

    • Author(s)
      Takuya Sakasai
    • Organizer
      Geometric Topology Fair 2017, KAIST (韓国)
    • Related Report
      2017 Annual Research Report
    • Int'l Joint Research / Invited
  • [Presentation] Johnson homomorphisms and symplectic representation theory2017

    • Author(s)
      Takuya Sakasai
    • Organizer
      Johnson homomorphisms and related topics, 東京大学
    • Related Report
      2017 Annual Research Report
    • Int'l Joint Research
  • [Presentation] Torelli group versus invariants of homology spheres and beyond2017

    • Author(s)
      Shigeyuki Morita
    • Organizer
      Johnson homomorphisms and related topics, 東京大学
    • Related Report
      2017 Annual Research Report
    • Int'l Joint Research / Invited
  • [Presentation] Invariants of homology cobordisms of surfaces2017

    • Author(s)
      Takuya Sakasai
    • Organizer
      Tsuda University Topology Workshop, 津田塾大学
    • Related Report
      2017 Annual Research Report
    • Invited
  • [Presentation] Characteristic classes of flat bundles and invariants of homology spheres2017

    • Author(s)
      Shigeyuki Morita
    • Organizer
      Topology and Geometry of Low-dimensional manifolds 2017, 奈良女子大学
    • Related Report
      2017 Annual Research Report
    • Int'l Joint Research / Invited
  • [Presentation] Cohomology of the moduli space of graphs and groups of homology cobordisms of surfaces2017

    • Author(s)
      逆井卓也
    • Organizer
      北海道大学大学院理学研究院数学部門 幾何学コロキウム, 北海道大学
    • Related Report
      2017 Annual Research Report
    • Invited
  • [Presentation] 自由群の acyclic closure とその自己同型群について2017

    • Author(s)
      逆井卓也
    • Organizer
      ストリングトポロジーとその周辺, 文部科学省共済組合箱根宿泊所
    • Related Report
      2017 Annual Research Report
  • [Presentation] Additive invariants of homology cobordisms of surfaces2017

    • Author(s)
      逆井卓也
    • Organizer
      大阪大学大学院理学研究科数学専攻・理学部数学科 談話会, 大阪大学
    • Related Report
      2017 Annual Research Report
    • Invited
  • [Presentation] On the dihedral invariant Lie subalgebra of the associative symplectic derivation Lie algebra2016

    • Author(s)
      逆井卓也
    • Organizer
      GD2016---微分同相群と離散群
    • Place of Presentation
      文部科学省共済組合箱根宿泊所 (神奈川県足柄下郡)
    • Year and Date
      2016-12-17
    • Related Report
      2016 Annual Research Report
  • [Presentation] Cohomology of the moduli space of graphs and groups of homology cobordisms of surfaces2016

    • Author(s)
      逆井卓也
    • Organizer
      トポロジー火曜セミナー
    • Place of Presentation
      東京大学 (東京都目黒区)
    • Year and Date
      2016-11-15
    • Related Report
      2016 Annual Research Report
  • [Presentation] An abelian quotient of the symplectic derivation Lie algebra of the free Lie algebra2016

    • Author(s)
      逆井卓也
    • Organizer
      トポロジーとコンピュータ 2016
    • Place of Presentation
      カレッジプラザ (秋田県秋田市)
    • Year and Date
      2016-10-29
    • Related Report
      2016 Annual Research Report
  • [Presentation] Characteristic classes of homological surface bundles and four-dimensional topology2016

    • Author(s)
      Shigeyuki Morita
    • Organizer
      Topology and Geometry of Low-dimensional manifolds 2016
    • Place of Presentation
      奈良女子大学 (奈良県奈良市)
    • Year and Date
      2016-10-25
    • Related Report
      2016 Annual Research Report
    • Int'l Joint Research / Invited
  • [Presentation] Topological approaches to Mumford-Morita-Miller classes2016

    • Author(s)
      Takuya Sakasai
    • Organizer
      MCM 2016
    • Place of Presentation
      沖縄科学技術大学院大学 (沖縄県恩納村)
    • Year and Date
      2016-10-24
    • Related Report
      2016 Annual Research Report
    • Int'l Joint Research
  • [Presentation] モジュライ空間の特性類 ~リーマン面,グラフ,ホモロジー同境~2016

    • Author(s)
      森田茂之
    • Organizer
      日本数学会2016年度秋季総合分科会 総合講演
    • Place of Presentation
      関西大学 (大阪府吹田市)
    • Year and Date
      2016-09-16
    • Related Report
      2016 Annual Research Report
    • Invited
  • [Presentation] An abelian quotient of the symplectic derivation Lie algebra of the free Lie algebra2016

    • Author(s)
      逆井卓也, 鈴木正明, 森田茂之
    • Organizer
      日本数学会2016年度秋期総合分科会 一般講演
    • Place of Presentation
      関西大学 (大阪府吹田市)
    • Year and Date
      2016-09-15
    • Related Report
      2016 Annual Research Report
  • [Presentation] Cohomology of the moduli space of graphs and groups of homology cobordisms of surfaces2016

    • Author(s)
      逆井卓也
    • Organizer
      離散群と双曲空間のトポロジーと解析
    • Place of Presentation
      京都大学数理解析研究所 (京都府京都市)
    • Year and Date
      2016-06-20
    • Related Report
      2016 Annual Research Report
    • Invited
  • [Presentation] Johnson-Morita theory(3回連続講演)2016

    • Author(s)
      Takuya Sakasai
    • Organizer
      Winter Braids VI
    • Place of Presentation
      Lille (France)
    • Year and Date
      2016-02-22
    • Related Report
      2015 Annual Research Report
    • Int'l Joint Research / Invited
  • [Presentation] Convex polytopes from fatgraphs2016

    • Author(s)
      逆井卓也
    • Organizer
      位相的漸化式入門
    • Place of Presentation
      木更津工業高等専門学校(千葉県木更津市)
    • Year and Date
      2016-01-30
    • Related Report
      2015 Annual Research Report
  • [Presentation] 自由群の外部自己同型群の有理コホモロジーについて2016

    • Author(s)
      逆井卓也
    • Organizer
      京都大学理学研究科/理学部数学教室談話会
    • Place of Presentation
      京都大学(京都府京都市)
    • Year and Date
      2016-01-06
    • Related Report
      2015 Annual Research Report
    • Invited
  • [Presentation] シンプレクティック微分リー代数とモジュライ空間のコホモロジー2015

    • Author(s)
      逆井卓也
    • Organizer
      広島大学大学院理学研究科数学専攻談話会
    • Place of Presentation
      広島大学(広島県東広島市)
    • Year and Date
      2015-12-01
    • Related Report
      2015 Annual Research Report
    • Invited
  • [Presentation] Integral Euler characteristic of the outer automorphism groups of free groups2015

    • Author(s)
      Masaaki Suzuki
    • Organizer
      Workshop on Automorphisms of Free Groups
    • Place of Presentation
      Copenhagen (Denmark)
    • Year and Date
      2015-11-10
    • Related Report
      2015 Annual Research Report
    • Int'l Joint Research / Invited
  • [Presentation] Structure of symplectic invariant Lie subalgebras associated with symplectic derivation Lie algebras2015

    • Author(s)
      Takuya Sakasai
    • Organizer
      Workshop on Automorphisms of Free Groups
    • Place of Presentation
      Copenhagen (Denmark)
    • Year and Date
      2015-11-10
    • Related Report
      2015 Annual Research Report
    • Int'l Joint Research / Invited
  • [Presentation] Structure of the Lie algebra of associative symplectic derivations2015

    • Author(s)
      Takuya Sakasai
    • Organizer
      RMT2015
    • Place of Presentation
      沖縄科学技術大学院大学(沖縄県恩納村)
    • Year and Date
      2015-11-03
    • Related Report
      2015 Annual Research Report
    • Int'l Joint Research / Invited
  • [Presentation] Tautological algebras of mapping class groups and representation theory2015

    • Author(s)
      Takuya Sakasai
    • Organizer
      MCM2015 autumn
    • Place of Presentation
      東京大学(東京都目黒区)
    • Year and Date
      2015-10-29
    • Related Report
      2015 Annual Research Report
    • Int'l Joint Research
  • [Presentation] Cohomology of automorphism groups of free groups2015

    • Author(s)
      Shigeyuki Morita
    • Organizer
      Topology and Geometry of Low-dimensional Manifolds, 2015
    • Place of Presentation
      奈良女子大学(奈良県奈良市)
    • Year and Date
      2015-10-29
    • Related Report
      2015 Annual Research Report
    • Int'l Joint Research / Invited
  • [Presentation] Homologically fibered knots and closed 3-manifolds2015

    • Author(s)
      逆井卓也
    • Organizer
      Mapping class groups and related topics on geometry and topology
    • Place of Presentation
      東京大学(東京都目黒区)
    • Year and Date
      2015-10-24
    • Related Report
      2015 Annual Research Report
  • [Presentation] Tautological algebra of mapping class group and representation theory2015

    • Author(s)
      森田茂之, 逆井卓也, 鈴木正明
    • Organizer
      日本数学会2015年度秋季総合分科会、一般講演
    • Place of Presentation
      京都産業大学(京都府京都市)
    • Year and Date
      2015-09-13
    • Related Report
      2015 Annual Research Report
  • [Presentation] 微分同相群とトポロジー ~特性類と不変量を中心として~2015

    • Author(s)
      森田茂之
    • Organizer
      第62回トポロジーシンポジウム
    • Place of Presentation
      名古屋工業大学(愛知県名古屋市)
    • Year and Date
      2015-08-08
    • Related Report
      2015 Annual Research Report
    • Invited
  • [Presentation] 写像類群の安定コホモロジー群について2015

    • Author(s)
      逆井卓也
    • Organizer
      種々の幾何学的構造と基本群に現れる様々な特性類とその不変量への応用
    • Place of Presentation
      KKR 下呂しらさぎ(岐阜県下呂市)
    • Year and Date
      2015-08-05
    • Related Report
      2015 Annual Research Report
    • Invited
  • [Presentation] 曲面の写像類群にまつわる話題2015

    • Author(s)
      逆井卓也
    • Organizer
      無限群と幾何学の周辺
    • Place of Presentation
      東京大学玉原国際セミナーハウス(群馬県沼田市)
    • Year and Date
      2015-07-12
    • Related Report
      2015 Annual Research Report
  • [Presentation] On homology cobordisms of surfaces of genus 12015

    • Author(s)
      Takuya Sakasai
    • Organizer
      離散群と双曲空間の幾何と解析
    • Place of Presentation
      京都大学数理解析研究所(京都府京都市)
    • Year and Date
      2015-06-25
    • Related Report
      2015 Annual Research Report
    • Invited
  • [Presentation] On homology cobordisms of surfaces of genus 12015

    • Author(s)
      Takuya Sakasai
    • Organizer
      French-Japanese workshop on Teichmueller spaces and surface mapping class groups
    • Place of Presentation
      Strasbourg (France)
    • Year and Date
      2015-06-05
    • Related Report
      2015 Annual Research Report
    • Int'l Joint Research / Invited
  • [Presentation] Tautological algebras of moduli spaces -survey and prospect-2015

    • Author(s)
      Shigeyuki Morita
    • Organizer
      RIMS 合宿型セミナー. Topology, Geometry and Algebra of low dimensional manifolds
    • Place of Presentation
      KKR 沼津はまゆう(静岡県沼津市)
    • Year and Date
      2015-05-25
    • Related Report
      2015 Annual Research Report
    • Int'l Joint Research / Invited
  • [Presentation] Non-meridional epimorphisms between knot groups2015

    • Author(s)
      Masaaki Suzuki
    • Organizer
      RIMS 合宿型セミナー. Topology, Geometry and Algebra of low dimensional manifolds
    • Place of Presentation
      KKR 沼津はまゆう(静岡県沼津市)
    • Year and Date
      2015-05-25
    • Related Report
      2015 Annual Research Report
    • Int'l Joint Research / Invited
  • [Presentation] 低次元トポロジーの謎 ~曲面およびグラフの族の特性類~2015

    • Author(s)
      森田茂之
    • Organizer
      大阪市立大学談話会
    • Place of Presentation
      大阪市立大学(大阪市住吉区)
    • Year and Date
      2015-05-07
    • Related Report
      2015 Annual Research Report
    • Invited
  • [Remarks] Homepage of Takuya SAKASAI

    • URL

      https://www.ms.u-tokyo.ac.jp/~sakasai/

    • Related Report
      2018 Annual Research Report
  • [Remarks] Homepage of Takuya SAKASAI

    • URL

      http://www.ms.u-tokyo.ac.jp/~sakasai/

    • Related Report
      2017 Annual Research Report 2015 Annual Research Report
  • [Funded Workshop] The 12th East Asian School of Knots and Related Topics2017

    • Place of Presentation
      東京大学 (東京都目黒区)
    • Year and Date
      2017-02-13
    • Related Report
      2016 Annual Research Report
  • [Funded Workshop] Johnson homomorphisms and related topics, 東京大学2017

    • Related Report
      2017 Annual Research Report
  • [Funded Workshop] New development in Teichmuller space theory; MCM2017, 沖縄科学技術大学院大学2017

    • Related Report
      2017 Annual Research Report
  • [Funded Workshop] Braids, Configuration Spaces and Quantum Topology2015

    • Place of Presentation
      東京大学(東京都目黒区)
    • Year and Date
      2015-09-07
    • Related Report
      2015 Annual Research Report

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Published: 2015-04-16   Modified: 2021-01-27  

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