2012 Fiscal Year Final Research Report

Studies on the quantum gravity effects in the early universe and black holes via string field theory and D-branes

Research Project

Project/Area Number	21740198
Research Category	Grant-in-Aid for Young Scientists (B)
Allocation Type	Single-year Grants
Research Field	Particle/Nuclear/Cosmic ray/Astro physics
Research Institution	Gunma National College of Technology
Principal Investigator	KOBAYASHI Shinpei 群馬工業高等専門学校, 一般教科(自然科学), 准教授 (70513901)
Project Period (FY)	2009 – 2012
Keywords	宇宙物理 / 素粒子論
Research Abstract	We investigated a three-dimensional gravitational theory on a noncommutative space which has a cosmological constant term only as a model which includes quantum gravity effects. We obtained various solutions that correspond to bubbles of spacetimes or interpolates zero metric and Minkowski metric and so on. All solutions we obtained are non-perturbative in the noncommutative parameter, therefore they are thought to be closely related to quantum gravity.We also investigated the fuzzy disc, which is a disc-shaped region in a noncommutative plane. We showed that one can introduce a concept of angles to the fuzzy disc, by using the phase operator and phase states known in quantum optics. As an application, we constructed fan-shaped soliton solutions of a scalar field theory on a fuzzy disc, which might correspond to a fan-shaped D-brane. We also applied this concept to an experimental test of noncommutativity by laser physics.

(6 results)