Institute for Gravitation and the Cosmos, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
Phys Rev Lett. 2013 Mar 29;110(13):131301. doi: 10.1103/PhysRevLett.110.131301. Epub 2013 Mar 26.
We study the behavior of n-point functions of the primordial curvature perturbations, assuming our observed Universe is only a subset of a larger space with statistically homogeneous and isotropic perturbations. If the larger space has arbitrary n-point functions in a family of local type non-gaussian statistics, sufficiently biased smaller volumes will have statistics from a "natural" version of that family with moments that are weakly non-gaussian and ordered, regardless of the statistics of the original field. We also describe the effect of this bias on the shape of the bispectrum.
我们研究了原始曲率扰动的 n 点函数的行为，假设我们所观察到的宇宙只是一个具有统计均匀和各向同性扰动的更大空间的一个子集。如果更大的空间在一族局部型非高斯统计中有任意 n 点函数，那么足够有偏差的较小体积将具有来自该族的“自然”版本的统计数据，其矩是弱非高斯且有序的，而不管原始场的统计数据如何。我们还描述了这种偏差对双谱形状的影响。
