Statistical Properties of Cosmological Fluctuations [chapter]

Peter Coles
2003 The Early Universe and the Cosmic Microwave Background: Theory and Observations  
In this pedagogical lecture, I introduce some of the basic terminology and description of fluctuating fields as they occur on cosmology. I define various statistical, cosmological and sample homogeneity and explain what is meant by the fair sample hypothesis and cosmic variance. I illustrate these concepts using the simplest second-order statistics, i.e. the two-point correlation function and its Fourier transform the power-spectrum. I then give a brief overview of the properties of information
more » ... relating to the properties of the phases of the Fourier modes of cosmological fluctuations which is not contained in these simpler statistics. Specifically, I explain how phase information of a particular form (called quadratic phase coupling) is encoded in the three-point correlation function (or, equivalently, the bispectrum).
doi:10.1007/978-94-007-1058-0_13 fatcat:hhr62swvlfh3fnexev673krwgm