Supersymmetry and Cosmology

我们在超引力的框架下研究了暴胀宇宙模型。在新暴胀模型中引入“预暴胀”，通过超引力效应来确定初始值，解决了初始值问题。这种“双重暴胀”模型导致了原始黑洞的产生或密度波动的功率谱的破碎。我们还构造了一个超引力下的混沌暴胀模型。我们研究了超对称模型中的重子生成问题，特别是研究了Q球和Affleck-Dine场的动力学，发现模型参数严格受Q球存在的约束，利用11维超引力中引力作用量的量子修正从四阶曲率开始，我们已经证明拓扑暴胀在这个理论中自然发生。我们还进一步证明了，为了再现曲率扰动的正确振幅，需要一个大的额外维数。我们提出了一个曲率扰动振幅下的超引力自然双暴胀模型。我们提出了一个超引力中的自然双暴胀模型，在这个模型中，不需要借助于Kahler势中的高阶项，就可以实现适当的再加热。我证明了，如果我们生活在一个有两个或多个简并真空的理论中的一个微扰真空态中，我们所观测到的宇宙学常数或暗能量就可以自然地得到解释。我们开发了一种形式主义，再现宇宙微波背景辐射的全天地图的曲率扰动的原始频谱。因此，我们可以获得早期宇宙暴胀时期粒子物理的重要信息。

We have studied inflationary universe models in the framework of supergravity. We have solved initial value problem in a new inflation model introducing "pre-inflation" which takes place before the new inflation and sets the initial vale through supergravity effects. This "double inflation" model leads to production of primordial black holes or a broken power spectrum of density fluctuations. We have also constructed a chaotic inflation model in supergravity. We have studied baryogenesis in SUSY models and, in particular, studied the dynamics of the Q-balls and Affleck-Dine field and have found that the model parameters are stringently constrained by the existence of the Q-ball.Making use of the fact that the quantum corrections to the gravitational action starts at the fourth order in curvature in 11 dimensional supergravity, we have shown that topological inflation naturally takes place in this theory. We have further shown that a large extra dimension is required in order to reproduce the correct amplitude of the curvature perturbations. We proposed a natural double inflation model in supergravity in amplitude of the curvature perturbations. We proposed a natural double inflation model in supergravity in which appropriate reheating is realized without resorting to higher order terms in Kahler potential, I showed that the observed cosmological constant or dark energy can naturally be explained if we live in one of the perturbative vacuum state in a theory with two or more degenerate vacua. We developed a formalism to reproduce the primordial spectrum of curvature perturbation out of the all-sky map of cosmic microwave background radiation. We can thereby obtain important information on particle physics at the inflation era in the early universe.