Study on physical laws behind Higgs boson looking forward ILC experiment

• Project/Area Number: 17K05413
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Particle/Nuclear/Cosmic ray/Astro physics
• Research Institution: Shinshu University
• Principal Investigator: Kawamura Yoshiharu 信州大学, 学術研究院理学系, 教授 (10224859)
• Project Period (FY): 2017-04-01 – 2022-03-31
• Project Status: Completed (Fiscal Year 2021)
• Budget Amount: ¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000); Fiscal Year 2021: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2020: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000); Fiscal Year 2019: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2018: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2017: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000)
• Keywords: ヒッグス粒子 / 質量階層性 / フレーバー混合 / フレーバー対称性 / 余剰次元 / オービフォールド / 自然さの問題 / 有効理論 / 湯川結合 / 微調整 / ベクターライクフェルミオン / ゲージ理論 / 世代の統合 / 素粒子論

Outline of Final Research Achievements

We have derived the standard model from Pati-Salam type model on a five-dimensional space-time, using an orbifold breaking and Coleman-Weinberg mechanism. We have derived enormous numbers of models with three families of the standard model matter multiplets from a massless Dirac fermion in a vectorlike representation of SU(N) gauge theory on a six-dimensional space-time. We have found that there is a possibility that the hierarchical flavor structure of quarks and charged leptons originates from non-canonical types of fermion kinetic terms in the presence of flavor-symmetric Yukawa interactions and a flavor symmetry can be hidden in the form of non-unitary bases in the standard model. We have clarified how a mechanism works to realize the hierarchy without severe fine tuning and a smallness of fermion masses is understood naturally.

Academic Significance and Societal Importance of the Research Achievements

素粒子の標準模型の構成要素であるヒッグス粒子や3世代の物質粒子（クォーク，レプトン）がより基本的な理論から導出され，また，物質粒子の構造（質量階層性，フレーバー混合）も理解される可能性が見出されたことにより，我々を含むこの宇宙の万物の存在が偶然ではなく必然として捉えることが可能になる。必然性を支持する存在理由が明らかになると，基本的な物理法則が我々の行う様々な知的活動における哲学的な基盤になる可能性が生まれる。

Research Products

• [Journal Article] On a mechanism realizing quark mass hierarchy (2020)
  • Author(s): Yoshiharu Kawamura
  • Journal Title: Modern Physics Letters A Volume: 35 Issue: 33 Pages: 2050274-2050274
  • DOI: 10.1142/s0217732320502740
  • Peer Reviewed
• [Journal Article] On diagonal representatives in boundary condition matrices on orbifolds (2020)
  • Author(s): Yoshiharu Kawamura and Noriyasu Nishikawa
  • Journal Title: International Journal of Modern Physics A Volume: 35 Issue: 31 Pages: 2050206-2050206
  • DOI: 10.1142/s0217751x20502061
  • Peer Reviewed
• [Journal Article] Chasing after flavor symmetries of quarks from the bottom up (2019)
  • Author(s): Yoshiharu Kawamura
  • Journal Title: Progress of Theoretical and Experimental Physics Volume: 2019 Issue: 7
  • DOI: 10.1093/ptep/ptz069
  • Peer Reviewed / Open Access
• [Journal Article] Yukawa interactions, flavor symmetry, and non-canonical Kaehler potential (2019)
  • Author(s): Kawamura Yoshiharu
  • Journal Title: Progress of Theoretical and Experimental Physics Volume: 2019 Issue: 4
  • DOI: 10.1093/ptep/ptz018
  • NAID: 130008151361
  • Peer Reviewed / Open Access
• [Journal Article] Orbifold family unification using vectorlike representation on six dimensions (2018)
  • Author(s): Goto Yuhei、Kawamura Yoshiharu
  • Journal Title: Physical Review D Volume: 98 Issue: 3
  • DOI: 10.1103/physrevd.98.035039
  • Peer Reviewed / Open Access
• [Journal Article] Left-right symmetry, orbifold S1/Z2, and radiative breaking of U(1)R × U(1)B-L (2018)
  • Author(s): Abe Yugo、Goto Yuhei、Kawamura Yoshiharu
  • Journal Title: Progress of Theoretical and Experimental Physics Volume: 2018 Issue: 10
  • DOI: 10.1093/ptep/pty095
  • Peer Reviewed / Open Access
• [Presentation] オービフォールド上の境界条件に関する表現行列における対角型表示について (2021)
  • Author(s): 川村嘉春
  • Organizer: 日本物理学会 第76回年次大会
• [Presentation] Study on quark mass hierarchy from the bottom up (2019)
  • Author(s): 川村嘉春
  • Organizer: 中部夏の学校
• [Presentation] 湯川相互作用，フレーバー対称性と非正準型ケーラーポテンシャル (2019)
  • Author(s): 川村嘉春
  • Organizer: 日本物理学会 2019年秋季大会
• [Presentation] Yukawa interactions, flavor symmetry, and democratic Kaehler structure (2018)
  • Author(s): 川村嘉春
  • Organizer: 中部夏の学校
• [Presentation] Left-right symmetry, orbifold S1/Z2, and radiative breaking of U(1)R×U(1)B-L (2018)
  • Author(s): 阿部裕悟，後藤裕平，川村嘉春
  • Organizer: 日本物理学会 2018年秋季大会
• [Presentation] 標準模型のフレーバー構造の起源の探究 (2018)
  • Author(s): 川村嘉春
  • Organizer: 質量階層性に対する新しい原理が導く多彩な物理現象とプランクスケールの物理
  • Invited
• [Presentation] Orbifold family unification using vectorlike representation (2018)
  • Author(s): 後藤裕平，川村嘉春
  • Organizer: 日本物理学会 第73回年次大会
• [Presentation] 5-dimensional left-right symmetric model (2017)
  • Author(s): 阿部裕悟，後藤裕平，川村嘉春，西川侃成
  • Organizer: 日本物理学会 2017年秋季大会
• [Presentation] 素粒子模型と例外群 (2017)
  • Author(s): 川村嘉春
  • Organizer: Exceptional Groups as Symmetries of Nature '17
  • Invited
• [Presentation] 素粒子物理 Overview (2017)
  • Author(s): 川村嘉春
  • Organizer: ILC 夏の学校 2017
  • Invited