Kolmogorov stochasticity parameter measuring the randomness in Cosmic Microwave Background

TL;DR

This paper applies the Kolmogorov stochasticity parameter to CMB temperature maps, revealing higher randomness in observational data compared to simulations and linking increased stochasticity to cosmic voids like the Cold Spot.

Contribution

It introduces the use of the Kolmogorov stochasticity parameter as a quantitative measure of randomness in CMB maps, highlighting its potential to identify cosmic voids.

Findings

WMAP5 maps show twice the randomness of simulated maps

The Cold Spot exhibits higher stochasticity, supporting its void nature

KSP can serve as a tracer for cosmic voids in the universe

Abstract

The Kolmogorov stochasticity parameter (KSP) is applied to quantify the degree of randomness (stochasticity) in the temperature maps of the Cosmic Microwave Background radiation maps. It is shown that, the KSP for the WMAP5 maps is about twice higher than that of the simulated maps for the concordance \LambdaCDM cosmological model, implying the existence of a randomizing effect not taken into account in the model. As was revealed recently, underdense regions in the large scale matter distributions, i.e the voids, possess hyperbolic and hence randomizing properties. The degree of randomness for the Cold Spot appears to be about twice higher than the average over the mean temperature level spots in the sky, which supports the void nature of the Cold Spot. Kolmogorov's parameter then acts as a quantitative tracer of the voids via CMB.