Cosmology and Effective Field Theory in Warped Extra Dimension

在粒子理论和宇宙学的交汇处存在着一些基本问题。为什么引力与其他基本力如此不同？为什么它这么弱（等级问题）？宇宙的暗能量是什么？是什么推动了暴胀，使宇宙平滑，同时孕育了结构的形成？弦理论和M理论需要额外的空间维度：它们如何解释我们所感知的三维宇宙？最近对最后一个问题——额外维度的研究，阐明了所有其他问题。在这个项目中，PI研究了一类额外的维度模型：那些额外的维度在3膜周围扭曲或弯曲的模型？一个捕获普通物质的三维子宇宙。弦理论和M理论预测了这样的膜；根据广义相对论，它们会扭曲时空；它们的翘曲将重力和粒子相互作用有效地呈现为3D。PI的工作是利用超维场论校准扭曲的粒子相互作用。因此，Braneworlds从一个更高的维度预测了一个明确的三维宇宙。此外，它们提供了一种动态的降维方法：由于在扭曲缺陷处形成了一个巨大的3膜，相变扭曲了额外维度中的一些场，自发地限制了重力和普通物质。年代的核心。

At the intersection of particle theory and cosmology lie fundamental questions. Why is gravity so different from other fundamental forces? Why is it so weak (the hierarchy problem)? What is the universe's dark energy? What drives inflation, smoothing the universe while seeding structure formation? String and M theories require extra spatial dimensions: how could they explain our perceived 3D universe? Recent work on this last question, extra dimension, illuminates all the others. In this project, the PI investigates a class of extra dimensional models: those where extra dimensions warp, or curve, around a 3-brane ? a 3D sub-universe trapping ordinary matter. Such branes are predicted by string and M theory; they warp space-time, due to general relativity; and their warp renders both gravity and particle interactions effectively 3D. The PI's work calibrates the warped particle interactions, using extra-dimensional field theory. Braneworlds thus predict a well-specified 3D universe, from one of higher dimension. Furthermore, they provide a dynamic means of dimensional reduction: a phase transition twists some field in the extra dimensions, spontaneously confining both gravity and ordinary matter, due to a massive 3-brane formed at the twisting defect?s core.