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

由星系耦合角动量引起的星系间椭圆度关联是一个有趣的研究课题。在理论方面，它们触及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，我们需要了解这些椭圆相关性，以便解释弱宇宙透镜效应，特别是估计宇宙学参数。在这个建议中，我想解决两个问题：如何以及椭圆跟踪潮汐剪切场和潮汐剪切相关函数看起来像在主轴框架的原生晕，这是唯一的物理相关性框架。

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.