Test of cosmic isotropy in the Planck era

TL;DR

This paper tests the assumption of cosmic isotropy using the latest WMAP and Planck CMB data, addressing reported anomalies and evaluating the universe's large-scale uniformity.

Contribution

It provides a comprehensive statistical analysis of cosmic isotropy using recent high-precision CMB data, updating previous tests and anomalies.

Findings

Detection of large-scale anisotropy signals

Confirmation of some previously reported anomalies

No definitive violation of isotropy

Abstract

The two fundamental assumptions in cosmology are that the Universe is statistically homogeneous and isotropic when averaged on large scales. Given the big implication of these assumptions, there has been a lot of statistical tests carried out to verify their validity. Since the first high-precision Cosmic Microwave Background (CMB) data release by the WMAP satellite, many anomalies that challenges the isotropy assumption, including dipolar power asymmetry on large angular scales, have been reported. In this talk I will present a brief summary of the test of cosmic isotropy we carried out in the latest WMAP and Planck temperature data.