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Unramified cohomology groups and rationality problem for fields of invariants

Research Project

Project/Area Number 19K03418
Research Category

Grant-in-Aid for Scientific Research (C)

Allocation TypeMulti-year Fund
Section一般
Review Section Basic Section 11010:Algebra-related
Research InstitutionNiigata University

Principal Investigator

Hoshi Akinari  新潟大学, 自然科学系, 教授 (50434262)

Co-Investigator(Kenkyū-buntansha) 山崎 愛一  京都大学, 理学研究科, 准教授 (10283590)
Project Period (FY) 2019-04-01 – 2023-03-31
Project Status Completed (Fiscal Year 2022)
Budget Amount *help
¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000)
Fiscal Year 2022: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000)
Fiscal Year 2021: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000)
Fiscal Year 2020: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000)
Fiscal Year 2019: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
Keywords有理性問題 / ネーター問題 / 不分岐コホモロジー / 半単項式作用 / 安定有理性 / レトラクト有理性 / 双有理分類 / ハッセ原理 / 不分岐ブラウアー群 / 代数的トーラス / ノルム1トーラス / ハッセノルム原理 / ダベンポート・ハッセの定理 / 不分岐コホモロジー群 / 整数ホッジ予想
Outline of Research at the Start

ネーター問題を含む不変体の有理性問題に対して,<1> 不分岐コホモロジー群と有理性問題;<2> 代数的トーラスの有理性問題とその応用;<3> 半単項式作用による不変体の有理性問題;<4> 代数幾何と数論のアルゴリズム開発とその応用の研究を行う.代数幾何,数論幾何,数論,群論,環論,表現論,計算代数における理論・手法を駆使し,当該分野の研究を先導してきたJ-P. Serre氏, D. Saltman氏, J.-L. Colliot-Thelene氏らの数学を発展させていく.理論的研究と計算による具体的な構成を行い,理論が具体例の計算を生み,具体例の計算が理論を生むことを目指す.

Outline of Final Research Achievements

About rationality problem for fields of invariants, we studied (1) Hasse norm principle for fields of degree <= 15 except for 12; (2) Davenport and Hasse's theorems and lifts of multiplication matrices of Gaussian periods; (3) Hasse norm principle for fields of degree 12; (4) multiplicative invariant fields of dimension <= 6; (5) a two-dimensional rationality problem and intersections of two quadrics; (6) three-dimensional purely quasi-monomial actions; (7) splitting fields of Lecacheux's family of quintic polynomials and rational points of associated elliptic curves; (8) norm one tori; (9) relation modules for dihedral groups; (10) degree three unramified cohomology; (11) algebraic tori of small dimensions, and we got several new results.

Academic Significance and Societal Importance of the Research Achievements

不変体の有理性問題に関する研究を行った。得られた研究成果は代数幾何、数論幾何、数論、群論、環論、表現論、計算代数の各分野に関連しており、各分野において重要な結果をいくつも含んでいる。ここで得られた具体例を元にして、理論が具体例の計算を生み、具体例の計算が理論を生む、好循環が生まれることが期待される。

Report

(5 results)
  • 2022 Annual Research Report   Final Research Report ( PDF )
  • 2021 Research-status Report
  • 2020 Research-status Report
  • 2019 Research-status Report
  • Research Products

    (36 results)

All 2023 2022 2021 2020 2019 Other

All Int'l Joint Research (4 results) Journal Article (11 results) (of which Int'l Joint Research: 4 results,  Peer Reviewed: 11 results,  Open Access: 1 results) Presentation (17 results) (of which Int'l Joint Research: 4 results,  Invited: 12 results) Book (2 results) Remarks (2 results)

  • [Int'l Joint Research] 国立台湾大学/国家理論科学研究中心(台湾)

    • Related Report
      2022 Annual Research Report
  • [Int'l Joint Research] 国立台湾大学/国家理論科学研究中心(台湾)

    • Related Report
      2021 Research-status Report
  • [Int'l Joint Research] 国立台湾大学/国家理論科学研究中心(台湾)

    • Related Report
      2020 Research-status Report
  • [Int'l Joint Research] 国立台湾大学/国家理論科学研究中心(台湾)

    • Related Report
      2019 Research-status Report
  • [Journal Article] Norm one tori and Hasse norm principle, II: Degree 12 case2023

    • Author(s)
      A. Hoshi, K. Kanai, A.Yamasaki
    • Journal Title

      Journal of Number Theory

      Volume: 244 Pages: 84-110

    • DOI

      10.1016/j.jnt.2022.09.006

    • Related Report
      2022 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Multiplicative Invariant Fields of Dimension ≦ 6.2023

    • Author(s)
      A.Hoshi, M.Kang, A.Yamasaki
    • Journal Title

      Memoirs of the American Mathematical Society

      Volume: 283 Issue: 1403 Pages: 1-137

    • DOI

      10.1090/memo/1403

    • Related Report
      2022 Annual Research Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] Norm one tori and Hasse norm principle2022

    • Author(s)
      A. Hoshi, K. Kanai, A.Yamasaki
    • Journal Title

      Mathematics of Computation

      Volume: 91 Issue: 337 Pages: 2431-2458

    • DOI

      10.1090/mcom/3735

    • Related Report
      2022 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Davenport and Hasse's theorems and lifts of multiplication matrices of Gaussian periods2022

    • Author(s)
      Hoshi Akinari, Kanai Kazuki
    • Journal Title

      Finite Fields and Their Applications

      Volume: 84 Pages: 1-26

    • DOI

      10.1016/j.ffa.2022.102101

    • Related Report
      2022 Annual Research Report
    • Peer Reviewed
  • [Journal Article] A two-dimensional rationality problem and intersections of two quadrics2021

    • Author(s)
      Akinari Hoshi, Ming-Chang Kang, Hidetaka Kitayama, Aiichi Yamasaki
    • Journal Title

      manuscripta mathematica

      Volume: - Issue: 3-4 Pages: 423-437

    • DOI

      10.1007/s00229-021-01313-7

    • Related Report
      2021 Research-status Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] On Lecacheux’s family of quintic polynomials2021

    • Author(s)
      Akinari Hoshi, Masakazu Koshiba
    • Journal Title

      Proceedings of the Japan Academy, Series A, Mathematical Sciences

      Volume: 97 Issue: 1 Pages: 1-6

    • DOI

      10.3792/pjaa.97.001

    • NAID

      40022466385

    • Related Report
      2020 Research-status Report
    • Peer Reviewed
  • [Journal Article] Rationality problem for norm one tori2021

    • Author(s)
      Akinari Hoshi, Aiichi Yamasaki
    • Journal Title

      Israel Journal of Mathematics

      Volume: 241 Issue: 2 Pages: 849-867

    • DOI

      10.1007/s11856-021-2117-1

    • Related Report
      2020 Research-status Report
    • Peer Reviewed
  • [Journal Article] Three-dimensional purely quasi-monomial actions2020

    • Author(s)
      Akinari Hoshi, Hidetaka Kitayama
    • Journal Title

      Kyoto Journal of Mathematics

      Volume: 60 Issue: 1 Pages: 335-377

    • DOI

      10.1215/21562261-2019-0008

    • Related Report
      2020 Research-status Report
    • Peer Reviewed / Open Access
  • [Journal Article] Degree three unramified cohomology groups and Noether's problem for groups of order 2432020

    • Author(s)
      Hoshi Akinari, Kang Ming-chang, Yamasaki Aiichi
    • Journal Title

      Journal of Algebra

      Volume: 544 Pages: 262-301

    • DOI

      10.1016/j.jalgebra.2019.08.008

    • Related Report
      2019 Research-status Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] Rationality problem for norm one tori in small dimensions2020

    • Author(s)
      Hasegawa Sumito, Hoshi Akinari, Yamasaki Aiichi
    • Journal Title

      Mathematics of Computation

      Volume: 89 Issue: 322 Pages: 923-940

    • DOI

      10.1090/mcom/3469

    • Related Report
      2019 Research-status Report
    • Peer Reviewed
  • [Journal Article] Rationality problems for relation modules of dihedral groups2019

    • Author(s)
      Hoshi Akinari, Kang Ming-chang, Yamasaki Aiichi
    • Journal Title

      Journal of Algebra

      Volume: 530 Pages: 368-401

    • DOI

      10.1016/j.jalgebra.2019.04.015

    • Related Report
      2019 Research-status Report
    • Peer Reviewed / Int'l Joint Research
  • [Presentation] Birational classification for algebraic tori2023

    • Author(s)
      Akinari Hoshi
    • Organizer
      湯布院代数幾何学ワークショップ
    • Related Report
      2022 Annual Research Report
    • Invited
  • [Presentation] Birational classification for algebraic tori (I)2023

    • Author(s)
      Akinari Hoshi, Aiichi Yamasaki
    • Organizer
      日本数学会2023年度年会
    • Related Report
      2022 Annual Research Report
  • [Presentation] Hasse norm principle for $M_{11}$ extensions2023

    • Author(s)
      Akinari Hoshi, Kazuki Kanai, Aiichi Yamasaki
    • Organizer
      日本数学会2023年度年会
    • Related Report
      2022 Annual Research Report
  • [Presentation] Birational classification for algebraic tori (I)2022

    • Author(s)
      Akinari Hoshi
    • Organizer
      新潟代数セミナー
    • Related Report
      2022 Annual Research Report
    • Invited
  • [Presentation] Birational classification for algebraic tori (III)2022

    • Author(s)
      Akinari Hoshi
    • Organizer
      新潟代数セミナー
    • Related Report
      2022 Annual Research Report
    • Invited
  • [Presentation] Hasse norm principle for $M_{11}$ extensions2022

    • Author(s)
      Akinari Hoshi
    • Organizer
      新潟代数セミナー
    • Related Report
      2022 Annual Research Report
    • Invited
  • [Presentation] Davenport and Hasse's theorems and lifts of multiplication matrices of Gaussian periods2021

    • Author(s)
      星明考,金井和貴
    • Organizer
      日本数学会2021年度秋季総合分科会
    • Related Report
      2021 Research-status Report
  • [Presentation] Rationality problem for fields of invariants2021

    • Author(s)
      星明考
    • Organizer
      名城大学理工学部数学科談話会
    • Related Report
      2021 Research-status Report
    • Invited
  • [Presentation] Rationality problem for fields of invariants2021

    • Author(s)
      Akinari Hoshi
    • Organizer
      Degenerations and models of algebraic varieties and related topics
    • Related Report
      2020 Research-status Report
    • Int'l Joint Research / Invited
  • [Presentation] Rationality problem for fields of invariants2021

    • Author(s)
      Akinari Hoshi
    • Organizer
      Homotopic and Geometric Galois Theory
    • Related Report
      2020 Research-status Report
    • Int'l Joint Research / Invited
  • [Presentation] Rationality problem for fields of invariants2020

    • Author(s)
      Akinari Hoshi
    • Organizer
      第18回代数曲線論シンポジウム
    • Related Report
      2020 Research-status Report
    • Invited
  • [Presentation] Norm one tori and Hasse norm principle2020

    • Author(s)
      Akinari Hoshi, Kazuki Kanai, Aiichi Yamasaki
    • Organizer
      日本数学会2020年度年会
    • Related Report
      2019 Research-status Report
  • [Presentation] Norm one tori and Hasse norm principle, II2020

    • Author(s)
      Akinari Hoshi, Kazuki Kanai, Aiichi Yamasaki
    • Organizer
      日本数学会2020年度年会
    • Related Report
      2019 Research-status Report
  • [Presentation] Degree three unramified cohomology groups and Noether's problem for groups of order 2432019

    • Author(s)
      Akinari Hoshi
    • Organizer
      NCTS Seminar on Algebra
    • Related Report
      2019 Research-status Report
    • Int'l Joint Research / Invited
  • [Presentation] Degree three unramified cohomology groups and Noether's problem for groups of order 2432019

    • Author(s)
      Akinari Hoshi
    • Organizer
      射影多様体の幾何とその周辺 2019
    • Related Report
      2019 Research-status Report
    • Invited
  • [Presentation] Rationality problem for fields of invariants2019

    • Author(s)
      Akinari Hoshi
    • Organizer
      第41回可換環論シンポジウム
    • Related Report
      2019 Research-status Report
    • Int'l Joint Research / Invited
  • [Presentation] Degree three unramified cohomology groups and Noether's problem for groups of order 2432019

    • Author(s)
      Akinari Hoshi
    • Organizer
      第15回多項式環論セミナー
    • Related Report
      2019 Research-status Report
    • Invited
  • [Book] 要点明解 線形数学 三訂版2022

    • Author(s)
      田中環,小島秀雄,星明考,折田龍馬,印南信宏,吉原久夫
    • Total Pages
      203
    • Publisher
      培風館
    • Related Report
      2022 Annual Research Report
  • [Book] 構成的ガロア逆問題と不変体の有理性問題(第27回整数論サマースクール報告集)2020

    • Author(s)
      小松亨、星明考、北山秀隆
    • Total Pages
      368
    • Publisher
      新潟大学学術リポジトリ
    • Related Report
      2019 Research-status Report
  • [Remarks] Akinari HOSHI's Home Page

    • URL

      http://mathweb.sc.niigata-u.ac.jp/~hoshi/index-j.html

    • Related Report
      2022 Annual Research Report 2021 Research-status Report 2020 Research-status Report 2019 Research-status Report
  • [Remarks] 新潟大学研究者総覧

    • URL

      http://researchers.adm.niigata-u.ac.jp/html/100000738_ja.html

    • Related Report
      2022 Annual Research Report 2021 Research-status Report 2020 Research-status Report 2019 Research-status Report

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Published: 2019-04-18   Modified: 2024-01-30  

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