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2011 Fiscal Year Final Research Report

Structures of the cohomology rings of the Torelli group and Lagrangian mapping class groups

Research Project

  • PDF
Project/Area Number 21740044
Research Category

Grant-in-Aid for Young Scientists (B)

Allocation TypeSingle-year Grants
Research Field Geometry
Research InstitutionTokyo Institute of Technology

Principal Investigator

SAKASAI Takuya  東京工業大学, 大学院・理工学研究科, 助教 (60451902)

Project Period (FY) 2009 – 2011
Keywords位相幾何 / 写像類群 / トレリ群 / Johnson準同型
Research Abstract

Johnson-Morita theory plays an important role in the study of subgroups of mapping class groups of surfaces called Lagrangian mapping class groups. We determined the images of the rational fifth and sixth Johnson homomorphisms and studied the structures of related Lie algebras(Joint work with Shigeyuki Morita and Masaaki Suzuki). In particular, we determined the abelianization of so-called "the associative case" and showed that the highest rational homology group of the moduli space of Riemann surfaces vanish.

  • Research Products

    (16 results)

All 2012 2011 2010 2009

All Journal Article (6 results) (of which Peer Reviewed: 4 results) Presentation (10 results)

  • [Journal Article] Lagrangian mapping class groups from a group homological point of view2012

    • Author(s)
      Takuya Sakasai
    • Journal Title

      Algebraic & Geometric Topology

      Volume: 12 Pages: 267-291

    • Peer Reviewed
  • [Journal Article] Homology cylinders and sutured manifolds for homologically fibered knots2012

    • Author(s)
      Hiroshi Goda, Takuya Sakasai
    • Journal Title

      Tokyo Journal of Mathematics

      Volume: (印刷中)

    • Peer Reviewed
  • [Journal Article] A survey of Magnus representations for mapping class groups and homology cobordisms of surfaces2012

    • Author(s)
      Takuya Sakasai
    • Journal Title

      Handbook of Teichmueller theory

      Volume: 3巻(印刷中)

  • [Journal Article] Johnson homomorphisms as fibering obstructions of homologically fibered knots2011

    • Author(s)
      Hiroshi Goda, Takuya Sakasai
    • Journal Title

      数理解析研究所講究録

      Volume: 1747 Pages: 47-66

  • [Journal Article] Factorization formulas and computations of higher-order Alexander invariants for homologically fibered knots2011

    • Author(s)
      Hiroshi Goda, Takuya Sakasai
    • Journal Title

      Journal of Knot Theory and Its Ramifications

      Volume: 20 Pages: 1355-1380

    • Peer Reviewed
  • [Journal Article] Abelian quotients of monoids of homology cylinders2011

    • Author(s)
      Hiroshi Goda, Takuya Sakasai
    • Journal Title

      Geometriae Dedicata

      Volume: 151 Pages: 387-396

    • Peer Reviewed
  • [Presentation] 曲面の写像類群と自由結合代数のシンプレクティック微分リー代数I, II2012

    • Author(s)
      逆井卓也
    • Organizer
      第6回福岡・札幌幾何学セミナー
    • Place of Presentation
      九州大学西新プラザ
    • Year and Date
      20120220-21
  • [Presentation] 自由結合代数のシンプレクティック微分のなすリー代数のアーベル化とその応用2011

    • Author(s)
      逆井卓也
    • Organizer
      東京理科大学理工学部数学科談話会
    • Place of Presentation
      東京理科大学
    • Year and Date
      2011-12-09
  • [Presentation] The Magnus representation and homology cobordism groups of homology cylinders2011

    • Author(s)
      Takuya Sakasai
    • Organizer
      GCOE workshop"Circle valued Morse theory and Alexander invariants"
    • Place of Presentation
      東京大学
    • Year and Date
      2011-11-18
  • [Presentation] 自由リー代数のシンプレクティック微分のなすリー代数の構造について2011

    • Author(s)
      逆井卓也
    • Organizer
      トポロジーとコンピュータ2011
    • Place of Presentation
      名城大学名駅サテライト
    • Year and Date
      2011-11-14
  • [Presentation] On a structure of the symplectic derivation Lie algebra of free Lie algebra(ポスター発表)2011

    • Author(s)
      Shigeyuki Morita, Takuya Sakasai, Masaaki Suzuki
    • Organizer
      Todai Forum 2011 "Geometry and Dynamics"
    • Place of Presentation
      Ecole normale superieure de Lyon(フランス)
    • Year and Date
      2011-10-17
  • [Presentation] 自由結合代数の微分のなすリー代数のアーベル化2011

    • Author(s)
      逆井卓也,鈴木正明
    • Organizer
      リーマン面に関連する位相幾何学
    • Place of Presentation
      東京大学
    • Year and Date
      2011-09-03
  • [Presentation] ohnson homomorphisms in knot theory2010

    • Author(s)
      Takuya Sakasai
    • Organizer
      Teichmueller theory
    • Place of Presentation
      Mathematisches Forschungsinstitut Oberwolfach(ドイツ)
    • Year and Date
      2010-12-03
  • [Presentation] The Magnus representation and the homology cobordism group of homology cylinders2010

    • Author(s)
      Takuya Sakasai
    • Organizer
      Teichmueller theory and its Interactions in Mathematics and Physics
    • Place of Presentation
      Centre de Recerca Matematica, Bellaterra(スペイン)
    • Year and Date
      2010-07-01
  • [Presentation] Homology cylinders and knot theory2010

    • Author(s)
      Takuya Sakasai
    • Organizer
      GCOE and Horiba International Symposium "Knots, Contact Geometry and Floer Homology"
    • Place of Presentation
      東京大学
    • Year and Date
      2010-05-24
  • [Presentation] agrangian mapping class groups from group homological point of view2009

    • Author(s)
      Takuya Sakasai
    • Organizer
      International Conference on Loops, strings and moduli spaces
    • Place of Presentation
      南開大学(中国)
    • Year and Date
      2009-08-03

URL: 

Published: 2013-07-31  

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