Dynamics of Spontaneous Symmetry Breaking and the Hosotani Mechanism

2018 Fiscal Year Final Research Report

• Project/Area Number: 15K05052
• 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: Osaka University
• Principal Investigator: Hosotani Yutaka 大阪大学, 理学研究科, 招へい研究員 (50324744)
• Project Period (FY): 2015-04-01 – 2019-03-31
• Keywords: 素粒子論 / ゲージ理論 / 余剰次元 / 細谷機構 / 対称性の自発的破れ

Outline of Final Research Achievements

Unification of forces implies large gauge symmetry. This large gauge symmetry must be spontaneously broken to smaller gauge symmetry to produce diverse forms of forces observed in Nature at low energies. In the standard model of elementary particle physics, the symmetry is broken by the Higgs mechanism. In this research project the gauge-Higgs unification theory was constructed, in which the large gauge symmetry is dynamically and spontaneously broken to smaller gauge symmetry by the Hosotani mechanism in place of the Higgs mechanism. The Higgs boson in four dimensions appears as the fifth dimensional component of the gauge fields. The signatures of the fifth dimension in spacetime can be observed in experiments at high energy colliders such as LHC and ILC.

Free Research Field

素粒子物理学

Academic Significance and Societal Importance of the Research Achievements

力の統合と対称性の自発的破れは表裏一体の関係にある。素粒子の標準理論ではヒッグス機構により対称性が破られる。本研究では、ヒッグス機構に代わって細谷機構により力学的にゲージ対称性が自発的に破れるゲージヒッグス統合理論を構築した。我々の時空は４次元ではなく、5次元目の空間があるとする。細谷機構は高次元空間のゲージ理論における量子効果でゲージ対称性が自発的に破れる。ヒッグスボゾンはゲージ場の一部となる。５次元目の存在を近い将来、高エネルギー加速器（LHC, ILC）で観測できることを示した。