Ellipticity correlations between galaxies, reconstructions of the cosmic density field, tidal shear correlations in the cosmic structure

由星系间角动量耦合引起的星系间椭圆度相关性是一个引人入胜的研究课题。在理论方面，它们触及了我们对宇宙结构形成和宇宙大尺度结构中的潮汐力的理解，这些潮汐力将角动量引入原星系，而在实践方面，我们需要理解这些椭圆率相关性，以便解释弱宇宙透镜效应，特别是对宇宙参数的估计。在这个提议中，我想解决两个问题：椭圆如何很好地跟踪潮汐切变场，以及潮汐切变相关函数在原晕的主轴框架中是如何表现的，这是唯一的物理相关框架。

Ellipticity correlations between galaxies which are caused by their coupled angular momenta are a fascinating research topic. On the theoretical side they touch our understanding of cosmic structure formation and the tidal forces in the cosmic large-scale structure, which induce angular momentum into protogalaxies, and on the practical side we require an understanding of these ellipticity correlations for our interpretation of the weak cosmic lensing effect, in particular for the estimation of cosmological parameters. In this proposal I would like to address two questions: How well do ellipticities trace the tidal shear field and how does the tidal shear correlation functions look like in the principal axis frame of the protohaloes, which is the only frame of physical relevance.