Testing for Non-Gaussianity on Cosmic Microwave Background Radiation: A Review

Abstract

Cosmic microwave background (CMB) radiation can be viewed as a snapshot of the Universe 13 billion years ago, when it had 0.002% of its current age. A flood of data on CMB is becoming available thanks to satellite and balloon-borne missions, and a number of statistical issues have been raised consequently. A very relevant issue is the characterization of the statistical distribution of CMB and, in particular, procedures to test the assumption that the generating random field is Gaussian. Gaussianity tests are of fundamental importance both to validate statistical inference procedures and to discriminate between competing scenarios for the Big Bang dynamics. Several procedures have been proposed in the cosmological literature. This article is an attempt to provide a brief survey of developments in this area.