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QUANTUM TRANSITIONS IN EARLY UNIVERSE IN THE STRING THEORY WITH T-DUALITY

具有 T 对偶性的弦理论中早期宇宙的量子跃迁

基本信息

批准号：
08640372
负责人：
KIKKAWA Keiji
金额：
$ 1.28万
依托单位：
Osaka University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1996
资助国家：
日本
起止时间：
1996 至 1997
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08640372/
关键词：
T-duality string cosmology winding mode Winding number conjugate space Type I-SST Type I'-SST Topological Field Theory D-5 brane Instanton D-brane 結合状態ディラトン

项目摘要

(1) We have studied the time development of a universe with a torus structure in a string theory. In such a topologically non-trivial space, the T-duality plays as essential role for its time development. When the space is large enough most of closed strings stay there as small loop gas. The space there, which we call the x-space, is defined as the one canonically conjugate to the center of mass momentum of the small loops. As the size of the x-space becomes small, the string winding modes around the torus dominate and the dynamics there is better described by the new space coodinate x, which is conjugate to the winding number w.In the first article in the publication list, we have studied the time development of the torus space with a special care for the transition from x-space to x-space in 2+1 dimensional model, taking account of the back ground gravity and torsion fields.In the fourth article, we studied the possibility of signal exchange between the x-space and x-space through the shinkage of the universe which occurs at the transition period from x- to x-space. Although the statistical average of coordinate correlation DELTAx・DELTAx approaches to zero, time development in the x-space after the transition makes it difficult to observe the information from the x space at the present time.(2) In the superstring theory Kunitomo et.al.constructed a generating functional of scattering amplitudes for Type I-SST,and found the mechanism how the divergence cancellation in Type I-SST can be interpreted in the dual theory Type I'. In the latter, the disk amplitudes which have boundaries on the orbifoled precisely cancel those associated with tadpole amplitudes.(3) Kunitomo et al also constructed a topological field theory which describes the ground states of D-5 branes. As a result they showed that the Heisenberg algebras in the instanton moduli space can be interpreted as creation and annihilation operators of the D-5 branes.

(1) 我们研究了弦理论中具有环面结构的宇宙的时间发展。在这样一个拓扑上非平凡的空间中，T-对偶性对其时间发展起着至关重要的作用。当空间足够大时，大多数闭合弦以小循环气体的形式停留在那里。那里的空间，我们称之为 x 空间，被定义为与小环的质心动量中心的正则共轭。随着 x 空间的尺寸变小，环面周围的弦缠绕模式占主导地位，并且新的空间坐标 x 可以更好地描述那里的动力学，该坐标与缠绕数 w 共轭。在出版物列表中的第一篇文章中，我们研究了环面空间的时间发展，特别关注 2+1 维模型中从 x 空间到 x 空间的过渡，考虑了背景重力和挠场。文章中，我们研究了在从x空间到x空间过渡期间发生的宇宙收缩，x空间和x空间之间信号交换的可能性。虽然坐标相关性DELTAx·DELTAx的统计平均值趋近于零，但跃迁后x空间中的时间发展使得观测当前时刻x空间的信息变得困难。(2)Kunitomo等人在超弦理论中构造了I型SST的散射振幅生成函数，并找到了I型SST中散度抵消的机制。解释为对偶理论类型 I'。在后者中，在轮叶上有边界的圆盘振幅精确地抵消了与蝌蚪振幅相关的振幅。(3)Kunitomo等人还构建了描述D-5膜基态的拓扑场论。结果，他们表明瞬时子模空间中的海森堡代数可以解释为 D-5 膜的创建和湮灭算子。