Exploring the origin of density fluctuations and the evolution of the early Universe in the precision cosmology era

2018 Fiscal Year Final Research Report

• Project/Area Number: 15K05084
• 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: Saga University
• Principal Investigator: Takahashi Tomo 佐賀大学, 理工学部, 准教授 (60432960)
• Project Period (FY): 2015-04-01 – 2019-03-31
• Keywords: 初期宇宙 / 精密宇宙観測 / 密度揺らぎ

Outline of Final Research Achievements

Recent precise cosmological observations have revealed various aspects of the Universe: the current energy budget of the Universe, the properties of primordial density fluctuations, and so on. Nevertheless, our understanding of the early Universe is still far from complete. In this research project, the evolution of the early Universe and the origin of density fluctuations have been explored, particularly focusing on small scale density fluctuations and gravity waves. By assuming concrete specifications of some future observations, we have analyzed expected constraints on models of the early Universe, then investigated what kind of models can be well tested by future observations. We believe that our findings have many implications for the research on the early Universe.

Free Research Field

宇宙論

Academic Significance and Societal Importance of the Research Achievements

本研究では、初期宇宙の研究ではこれまであまり考えられていなかった観測（量）についても、初期宇宙進化、および、密度揺らぎの起源モデルの検証に有用であることを、具体的に幾つかのモデルにおける理論予言の解析も行いつつ示した。この点は本研究の意義深い点の一つである。
初期宇宙進化、密度揺らぎの起源を探る研究は、究極的には宇宙誕生の謎に迫る架け橋となる研究であり、究極的な根源知を追求するもので、人類の文化の蓄積に資するものと考えている。この点が本研究の社会的意義である。