Formulation of elementary processes in strong electromagnetic field and its application to high-energy phenomena

2023 Fiscal Year Final Research Report

• Project/Area Number: 22K14045
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 15010:Theoretical studies related to particle-, nuclear-, cosmic ray and astro-physics
• Research Institution: Institute of Physical and Chemical Research
• Principal Investigator: Hidetoshi Taya 国立研究開発法人理化学研究所, 数理創造プログラム, 基礎科学特別研究員 (30807970)
• Project Period (FY): 2022-04-01 – 2024-03-31
• Keywords: 強い場の物理 / 非摂動効果 / 非平衡過程 / 量子電磁力学 / Schwinger機構 / Schwinger効果 / 粒子生成

Outline of Final Research Achievements

A physical system exhibits intriguing nonlinear responses when exposed to a strong electromagnetic field. Such strong-electromagnetic-field processes are not well understood both theoretically and experimentally, and therefore are of fundamental importance. Strong electromagnetic fields are generated in actual physical systems under various extreme conditions, and the accompanying nonlinear processes play an important phenomenological role. To elucidate strong-electromagnetic-field physics, we have completed the formulation of elementary processes of scattering and radiation in strong electromagnetic fields by utilizing the scattering theory in unstable vacuum and the semiclassical approximation. We have applied this formulation to a broad range of physical processes and systems (including vacuum birefringence, vacuum permittivity, chirality generation, reheating in the early Universe, and heavy-ion collisions) and clarified the phenomenological consequences strong fields.

Free Research Field

原子核理論

Academic Significance and Societal Importance of the Research Achievements

電球や太陽など、私たちの周りは様々な光で満ちている。身近な光はただ眩しいだけだが、強度を強くすると、虫眼鏡で紙が燃えたりレーザー加工ができたり、非自明なことが起こり出す。すると「光を極限的に強くすると何が起こるのか？」という疑問が浮かぶ。本研究は、この疑問の理論的解明を目指した研究である。極限的に強い光は、従来理論では記述できない非線形な物理過程を引き起こす。この非線形過程は単なる学術的対象ではなく、宇宙などの現実の極限環境で重要な現象論的な役割も果たす。本研究によって、こうした非線形過程を記述する基礎理論が完成し、また、それにより現実の極限系で強い電磁場が果たす現象論的役割の理解が深まった。