Topology of the Universe and Global Structure

Akio细谷：(1)我们研究了基于瑟斯顿定理的紧凑而均匀的宇宙模型的分类，发展了曲率和泰希穆勒参数的哈密顿描述。(2)我们将重整化群方程应用于含尘埃物质的爱因斯坦方程，并研究了不动点附近的重整化群流。(3)我们计算了引力波在旋转的大质量恒星上的绕射和干涉效应，发现像移了与旋转透镜的特定角动量成正比的距离。(4)我们发展了一种用有限能量波包探测类时奇点的理论，并证明了大多数已知的裸奇点实际上是无害的。石原英树：(1)研究了磁区壁和引力波的动力学，发现在Nambu-Goto类型的情况下，磁区壁完全吸收了引力波的自由度。(2)研究了光在非均匀宇宙模型中的传播，研究了不均匀对距离和红移的影响。

Akio Hosoya :(1) We have studied the classification of compact and homogeneous universe models based on Thurston's theorem and developed the Hamiltonian description of thecuravature and Teichmuller parameters.(2) We applied the renormalization group equation to the Einstein equation with dust matter and studied the renormalization group flow near the fixed point.(3) We calculated the effect of diffraction and interference of gravitational wave by a rotating massive star and found that the image shifts by a distance proportional to the specific angular momentum of the rotating lens.(4) We have developed a theory in which we probe timelike singularities by finite energy wave packet and showed that most of the known naked singularities are actually harmless. Namely, the wave propagation is perfectly well-defined in that spacetime.Hideki Ishihara :(1) The dynamics of domain wall and graviational wave has been studied and it is found that the degrees of freedom of gravitational wave is completely absorbed bt the domain wall in the case of the Nambu-Goto type.(2) We have studied the propagation of light in an inhomogeneous universe model and studies the effect of inhomogeneities to the distance and red-shift.