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Eigenvalues of Cartan matrices and Morita equivalences of blocks in finite groups

Research Project

Project/Area Number 21540009
Research Category

Grant-in-Aid for Scientific Research (C)

Allocation TypeSingle-year Grants
Section一般
Research Field Algebra
Research InstitutionTokyo University of Agriculture and Technology

Principal Investigator

WADA Tomoyuki  東京農工大学, 大学院・工学研究院, 教授 (40003008)

Co-Investigator(Renkei-kenkyūsha) YAMAGATA Kunio  東京農工大学, 大学院・工学研究院, 教授 (60015849)
KIYOTA Masao  東京医科歯科大学, 教養部, 教授 (50214911)
FUKUSHIMA Hiroshi  群馬大学, 教育学部, 教授 (30125869)
KUNUGI Naoko  東京理科大学, 理学部, 准教授 (50362306)
Project Period (FY) 2009 – 2011
Project Status Completed (Fiscal Year 2011)
Budget Amount *help
¥3,770,000 (Direct Cost: ¥2,900,000、Indirect Cost: ¥870,000)
Fiscal Year 2011: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000)
Fiscal Year 2010: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000)
Fiscal Year 2009: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
Keywords群の表現論 / 対称群 / 2-ブロック / 既約Brauer指標 / 高さ / カルタン行列 / 固有値 / 不足群 / 固有値の整数性 / 有限群 / ブロック / シュペヒト加群 / 中山の予想 / 一般指標 / ブルエ予想
Research Abstract

Let G be a finite group and H be a normal subgroup of G with p'-index. Let B be a p-block of G and b be any p-block of H covered by B. Then in Theorem 1. 1 of the work of Okuyama-Wada[ Okuyama-Wada, Contemp. Math., 524, 2010], we have proved that the largest eigenvalues of B and b are equal. Furthermore, we have proved that if B satisfies a certain condition(#) on the degrees of irreducible Brauer characters in B, then there exists an eigenvalueλof B such that the(π)-part ofλis equal to the order of defect group D of B. Any p-block of p-solvable group satisfies(#), but it does not hold in general. There exist counter examples for p> 3, however we could not find a counter example for p=2. How is a 2-block of the symmetric group? Calculating the degrees of irreducible Brauer characters, any 2-block of the symmetric group seems to satisfy(#). Furthermore, Kiyota, Okuyama and Wada have recently proved a stronger result than(#) that any 2-block of the symmetric group of arbitrary degree has a unique irreducible Brauer character of height 0[ Kiyota-Okuyama-Wada, accepted]. This generalizes the theorem of Fong, James that the degree of every non-trivial irreducible 2-Brauer characters of the symmetric group is even. This theorem has never been known. We could not discover this remarkable fact if we would not consider eigenvalues of the Cartan matrices of finite groups.

Report

(4 results)
  • 2011 Annual Research Report   Final Research Report ( PDF )
  • 2010 Annual Research Report
  • 2009 Annual Research Report
  • Research Products

    (33 results)

All 2012 2011 2010 2009 Other

All Journal Article (13 results) (of which Peer Reviewed: 10 results) Presentation (15 results) Book (2 results) Remarks (3 results)

  • [Journal Article] The heights of irreducible Brauer characters in 2-blocks of the symmetric groups2012

    • Author(s)
      M. Kiyota, T. Okuyama, T. Wada
    • Journal Title

      Journal of Algebra

      Pages: 18-18

    • Related Report
      2011 Final Research Report
    • Peer Reviewed
  • [Journal Article] 対称群の2-ブロックにおける高さOの既約Brauer指標について2012

    • Author(s)
      清田正夫・奥山哲郎・和田倶幸
    • Journal Title

      数理解析研究所講究録

      Volume: (印刷中)(掲載決定)

    • Related Report
      2011 Annual Research Report
  • [Journal Article] On selfinjective Artin algebras having generalized standard quasitubes2011

    • Author(s)
      Maciej Karpicz, Andrzej Skowronski, Kunio Yamagata
    • Journal Title

      Journal of Pure and Applied Algebra

      Volume: 215巻11号 Pages: 2738-2760

    • Related Report
      2011 Final Research Report
    • Peer Reviewed
  • [Journal Article] On saturated fusion systems and Brauer indecomposability of Scott modules2011

    • Author(s)
      R. Kessar, N. Kunugi, N. Mitsuhashi
    • Journal Title

      Journal of Algebra

      Volume: 340巻1号 Pages: 90-103

    • Related Report
      2011 Final Research Report
    • Peer Reviewed
  • [Journal Article] The heights of irreducible Brauer characters in 2-blocks of the symmetric groups2011

    • Author(s)
      清田正夫・奥山哲郎・和田倶幸
    • Journal Title

      第28回代数的組み合わせ論シンポジウム報告集

      Volume: 28 Pages: 40-917

    • Related Report
      2011 Annual Research Report
  • [Journal Article] Eigenvalues of Cartan matrices of blocks in finite groups2010

    • Author(s)
      Tetsuro Okuyama, Tomoyuki Wada
    • Journal Title

      Contemporary Mathematics, Amer. Math. Soc

      Volume: 542 Pages: 127-138

    • Related Report
      2011 Final Research Report
    • Peer Reviewed
  • [Journal Article] Trivial source modules in blocks with cyclic defect groups2010

    • Author(s)
      S. Koshitani, N. Kunugi
    • Journal Title

      Mathematische Zeitschrift

      Volume: 265巻1号 Pages: 1161-172

    • Related Report
      2011 Final Research Report
    • Peer Reviewed
  • [Journal Article] Blocks with nonabelian defect groups which have cyclic subgroups of index2010

    • Author(s)
      M. Holloway, S. Koshitani, N. Kunugi
    • Journal Title

      Archiv der Mathematik(Basel)

      Volume: 94巻2号 Pages: 101-116

    • Related Report
      2011 Final Research Report
    • Peer Reviewed
  • [Journal Article] Eigenvalues of Cartan matrices of blocks in finite groups2010

    • Author(s)
      T.Okuyama T.Wada
    • Journal Title

      Contemporary Mathematics(アメリカ数学会)

      Volume: 524 Pages: 127-138

    • Related Report
      2010 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Eigenvalues of Cartan matrices of blocks in finite groups2010

    • Author(s)
      T.Okuyama, 和田倶幸
    • Journal Title

      Contemporary Mathematics(アメリカ数学会) (印刷中)

    • Related Report
      2009 Annual Research Report
    • Peer Reviewed
  • [Journal Article] 有限次元自己入射多元環の表現とその周辺2009

    • Author(s)
      Kunio Yamagata
    • Journal Title

      日本数学会編集「数学」

      Volume: 61巻3号 Pages: 270-292

    • NAID

      10026415268

    • Related Report
      2011 Final Research Report
    • Peer Reviewed
  • [Journal Article] Irreducible products of characters of solvable groups2009

    • Author(s)
      Hiroshi Fukushima
    • Journal Title

      Journal of Algebra

      Volume: 321 Pages: 312-315

    • Related Report
      2011 Final Research Report
    • Peer Reviewed
  • [Journal Article] p-可解群におけるカルタン行列の固有値の整数性について2009

    • Author(s)
      和田倶幸
    • Journal Title

      有限群論草津セミナー報告集 21

      Pages: 85-90

    • Related Report
      2009 Annual Research Report
  • [Presentation] The heights of irreducible Brauer characters in 2-blocks of the symmetric groups2011

    • Author(s)
      Tomoyuki Wada
    • Organizer
      Algebra Seminar, Friedrich Schiller University at Jena
    • Place of Presentation
      Germany
    • Year and Date
      2011-09-22
    • Related Report
      2011 Final Research Report
  • [Presentation] 対称群の2-ブロックにおける既約Brauer指標の高さ2011

    • Author(s)
      Tetsuro Okuyama, Masao Kiyota, Tomoyuki Wada
    • Organizer
      有限群のコホモロジーとその周辺シンポジウム
    • Place of Presentation
      京都大学数理解析研究所
    • Year and Date
      2011-09-01
    • Related Report
      2011 Final Research Report
  • [Presentation] Fusion systemとスコット加群のBrauer直既約性2011

    • Author(s)
      Naoko Kunugi
    • Organizer
      有限群のコホモロジーとその周辺シンポジウム
    • Place of Presentation
      京都大学数理解析研究所
    • Year and Date
      2011-08-29
    • Related Report
      2011 Final Research Report
  • [Presentation] 対称群における2-modular既約加群の2-height2011

    • Author(s)
      Tetsuro Okuyama, Masao Kiyota, Tomoyuki Wada
    • Organizer
      第28回代数的組み合わせ論シンポジウム
    • Place of Presentation
      大分大学
    • Year and Date
      2011-06-20
    • Related Report
      2011 Final Research Report
  • [Presentation] The heights of irreducible Brauer characters in 2-blocks of the symmetric groups2011

    • Author(s)
      和田倶幸
    • Organizer
      第28回代数的組み合わせ論シンポジウム
    • Place of Presentation
      大分大学工学部
    • Year and Date
      2011-06-20
    • Related Report
      2011 Annual Research Report
  • [Presentation] Scott modules and blocks of finite groups2011

    • Author(s)
      Naoko Kunugi
    • Organizer
      Workshop "Global/local conjectures in representation theory of finite groups"
    • Place of Presentation
      Banff International Resarch Station(Canada)
    • Year and Date
      2011-03-17
    • Related Report
      2011 Final Research Report
  • [Presentation] Cartan eigenvalues of blocks of finite groups2010

    • Author(s)
      Tomoyuki Wada
    • Organizer
      日本数学会
    • Place of Presentation
      名古屋大学
    • Year and Date
      2010-09-22
    • Related Report
      2011 Final Research Report
  • [Presentation] Generalized characters and Cartan eigenvalues in finite groups, The XIVth International Conference on Representations of Algebras2010

    • Author(s)
      Tomoyuki Wada
    • Organizer
      国立オリンピック記念青少年センター
    • Place of Presentation
      東京
    • Year and Date
      2010-08-15
    • Related Report
      2011 Final Research Report
  • [Presentation] Generalized characters and Cartan eigenvalues in finite groups2010

    • Author(s)
      T.Wada
    • Organizer
      International Conference on Representations of Algebras
    • Place of Presentation
      国立オリンピック記念青少年センター(東京都)
    • Year and Date
      2010-08-15
    • Related Report
      2010 Annual Research Report
  • [Presentation] On selfinjective Artin algebras having generalized standard quasitubes, The XIVth International Conference on Representations of Algebras2010

    • Author(s)
      Maciej Karpicz, Andrzej Scowro. ski, Kunio Yamagata
    • Organizer
      国立オリンピック記念青少年センター
    • Place of Presentation
      東京
    • Year and Date
      2010-08-12
    • Related Report
      2011 Final Research Report
  • [Presentation] Scott modules and equivalences between blocks of finite groups2010

    • Author(s)
      Naoko Kunugi
    • Organizer
      Algebra Seminar
    • Place of Presentation
      University of Aberdeen(UK)
    • Year and Date
      2010-03-18
    • Related Report
      2011 Final Research Report
  • [Presentation] Morita equivalent blocks of general linear groups in non-defining characteristic2009

    • Author(s)
      Naoko Kunugi
    • Organizer
      RIMS研究集会「代数的組合せ論および関連する群と代数」
    • Place of Presentation
      信州大学
    • Year and Date
      2009-11-20
    • Related Report
      2011 Final Research Report
  • [Presentation] Morita equivalences for general linear groups in non-defining characteristic2009

    • Author(s)
      Naoko Kunugi
    • Organizer
      RIMS研究集会「代数的三角圏とその周辺」
    • Place of Presentation
      京都大学
    • Year and Date
      2009-07-22
    • Related Report
      2011 Final Research Report
  • [Presentation] Eigenvalues of Cartan matrices of finite groups2009

    • Author(s)
      和田倶幸
    • Organizer
      Conference on Character Theory of Finite Groups
    • Place of Presentation
      スペイン・バレンシア大学
    • Year and Date
      2009-06-03
    • Related Report
      2009 Annual Research Report
  • [Presentation] Eigenvalues of Cartan matrices of finite groups2009

    • Author(s)
      Tomoyuki Wada
    • Organizer
      Isaacs Conference, University of Valencia
    • Place of Presentation
      Spain
    • Related Report
      2011 Final Research Report
  • [Book] European Mathematical Society(EMS)2011

    • Author(s)
      Andrzej Skowronski and Kunio Yamagata
    • Publisher
      Frobenius algebras
    • Related Report
      2011 Final Research Report
  • [Book] Representaions of algebras and related topics2011

    • Author(s)
      Andrzej Skowronski, Kunio Yamagata
    • Publisher
      Eur. Math. Soc.
    • Related Report
      2011 Final Research Report
  • [Remarks]

    • URL

      http://www.tuat.ac.jp/~wada

    • Related Report
      2011 Final Research Report
  • [Remarks]

    • URL

      http://www.tuat.ac.jp./~wada

    • Related Report
      2011 Annual Research Report
  • [Remarks]

    • URL

      http://www.tuat.ac.jp/~wada

    • Related Report
      2010 Annual Research Report

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Published: 2009-04-01   Modified: 2016-04-21  

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