Analysis of the superluminal modes by gravitational quantum effect

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K14281
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Particle/Nuclear/Cosmic ray/Astro physics
• Research Institution: Nagoya University
• Principal Investigator: Izumi Keisuke 名古屋大学, 素粒子宇宙起源研究所, 助教 (90554501)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 因果構造 / 時間発展のユニタリ性 / 重力理論

Outline of Final Research Achievements

The purpose of this project is to understand the quantum gravity by investigating the classical causality and its quantum object unitarity.
In the classical research, the concept of photon surface, that is defined only in static spacetimes, is extended to generic spacetimes. It has been shown that the area of the extended photon surface has an upper bound, and the hoop conjecture for it is established in some examples.
In the quantum research, the conjecture between unitarity and renormalizability is investigated. Although theories with higher derivatives are its counter examples, we have introduced a new concept S-matrix unitarity, and posited a new conjecture between S-matrix unitarity and renormalizability. We have seen our conjecture is established even in theories with higher derivatives.

Free Research Field

重力理論

Academic Significance and Societal Importance of the Research Achievements

古典的研究で扱った光球面は、ブラックホールの影の観測で見ている対象である。それを深く理解することで、重力理論の検証を精密に行うことができるようになった。
一方、ユニタリ性や繰り込み可能性は、量子重力理論を構築する際に克服するべき重要な問題点である。本研究は、その間の関係性を見出し、量子重力理論の理解につながる結果を得た。