SIMBAD references

2020MNRAS.495.4291C - Mon. Not. R. Astron. Soc., 495, 4291-4296 (2020/July-2)

Re-examining the evidence of the Hercules-Corona Borealis Great Wall.

CHRISTIAN S.

Abstract (from CDS):

In the lambda cold dark matter paradigm of cosmology, anisotropies larger than 260 Mpc should not exist. However, the existence of the Hercules-Corona Borealis Great Wall (HCB) is purported to challenge this principle by some with an estimated size exceeding 2000 Mpc. Recently, some have challenged the assertion of the existence of the HCB, attributing the anisotropy to sky exposure effects. It has never been explained why the original methods purporting the existence of the HCB produce anisotropies, even if sky-exposure effects are taken into account. In this paper, I apply the methods of the original papers purporting the existence of the HCB in various Monte Carlo simulations that assume isotropy to analyse the empirical meaning of the significance levels of the original tests used. I find that, although the statistical tests at first glance show significant anisotropies present in the suspect sample, Monte Carlo simulations can easily reproduce the sample in most cases, and if not, the differences can be accounted for by other statistical considerations. An updated sample raises the probability of drawing the observed clustering from an isotropic sample ten-fold in some cases. Thus the statistical tests used in prior studies overestimate the significance of the observed anisotropy, and an updated sample returns even less significant probabilities. Given the ability to reproduce the observed anisotropy in Monte Carlo simulations, the new, higher probabilities of being drawn from isotropy for an updated sample, and the work of previous papers attributing anisotropies to sky-selection effects, the existence of the HCB must be treated as doubtful at best.

Abstract Copyright: © 2020 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society

Journal keyword(s): large-scale structure of Universe - gamma-ray bursts

Simbad objects: 2

goto Full paper

goto View the references in ADS

To bookmark this query, right click on this link: simbad:2020MNRAS.495.4291C and select 'bookmark this link' or equivalent in the popup menu