Brane Gravity and Fundamental Problems in Cosmology

膜引力和宇宙学的基本问题

• 批准号: 17540268
• 负责人: MAEDA Kei-ichi
• 金额: $ 2.18万
• 依托单位: Waseda University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2005
• 资助国家: 日本
• 起止时间: 2005 至 2006
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-17540268/
• 关键词: cosmology; brane gravity; dark energy; string theory; general relativity; cosmological constant; black hole; inflation

New idea of gravitation is given from a "brane" in string theory, and it has recently been intensively studied because it may lead to new paradigm of cosmology. In the present research project, we have analyzed systematically fundamental problems in cosmology from the view point of a brane world in order to study new subjects such as what is the fundamental and important in brane gravity or what will be new paradigm of brane cosmology. Especially, studying new gravitational theory with a brane, we have discussed most important subjects in cosmology such as "dark energy", "cosmological constant problem", "creation of the universe" and "cosmological singularity". We have analyzed mainly the following three subjects:(1) The study of the unconventional early universe models based on brane collisionTaking into account self-gravity, we have analyzed a brane collision and shown that a spacetime singularity is formed because of gravitational instability. We have also studied the possibility of creation of matter (the origin of matter) in the universe via a brane collision.(2) The study of the inflation models based on string theoryWe have proposed new inflationary model based on string theory. We have studied the higher curvature terms which appear via quatum corrections in superstring theory. Although we find sufficient expansion of the universe, we need a fine tuning of initial conditions. It suggests that we have to find the proper correction terms with the Ricci curvature tensor as well as the Riemann one.(3) The construction of black hole solutions based on string theoryWe have presented new method to find black hole solutions in string theory. It is generalization of the conventional method using the BPS equations. We have obtained a new black hole (a caged black hole) solution.

从弦理论中的“膜”出发，提出了引力的新概念，由于它可能导致宇宙学的新范式，近年来得到了广泛的研究。本研究计划从膜世界的角度系统地分析了宇宙学中的基本问题，以期研究膜引力的基本和重要性以及膜宇宙学的新范式等新课题。特别是通过对新的引力理论的研究，我们讨论了宇宙学中的一些重要问题，如“暗能量”、“宇宙常数问题”、“宇宙的创生”和“宇宙奇点”等。（1）基于膜碰撞的非常规早期宇宙模型的研究在考虑自引力的情况下，我们分析了膜碰撞，指出了由于引力不稳定性而形成的时空奇点。我们还研究了通过膜碰撞在宇宙中创造物质（物质的起源）的可能性。(2)基于弦理论的暴胀模型的研究我们提出了一个新的基于弦理论的暴胀模型。我们研究了超弦理论中通过量子修正而出现的高曲率项。虽然我们发现宇宙有足够的膨胀，但我们需要对初始条件进行微调。这表明，我们必须找到适当的校正项与里奇曲率张量以及黎曼之一。(3)基于弦理论的黑洞解的构造我们提出了一种在弦理论中寻找黑洞解的新方法。这是对传统的BPS方程法的推广。我们得到了一个新的黑洞（笼中黑洞）解。

项目成果

Collision of Thick Branes(招待講演)

厚脑的碰撞（特邀报告）

• 发表时间: 2006
• 作者: 川村静児;他;Kei-ichi Maeda
• 通讯作者: Kei-ichi Maeda

スペース重力波アンテナDECIGO計画V

空间引力波天线DECIGO Project V

• 发表时间: 2006
• 作者: 川村静児;他
• 通讯作者: 他

重力理論入門(数理科学 連載)(2006年5、6、8、9、11、12月号、2007年2、3月号)

引力理论概论（数学科学系列）（2006年5月、6月、8月、9月、11月、12月号、2007年2月、3月号）

• 发表时间: 2007
• 作者: 吉田仁;前田恵一;John D.Barrow;Kei-ichi Maeda;Kei-ichi Maeda;Kei-ichi Maeda;Kei-ichi Maeda;Kei-ichi Maeda;Kei-ichi Maeda;前田恵一
• 通讯作者: 前田恵一

Collision of domain walls in asymptotically anti de Sitter spacetime

渐近反德西特时空中的磁畴壁碰撞

• 发表时间: 2006
• 期刊: Physical Review D73:103508
• 作者: Yu-ichi Takamizu;Kei-ichi Maeda
• 通讯作者: Kei-ichi Maeda

Fermions on colliding branes

• DOI: 10.1016/j.physletb.2007.01.042
• 发表时间: 2006-10
• 期刊: Physics Letters B
• 影响因子: 4.4
• 作者: G. Gibbons;K. Maeda;Yuichi Takamizu