Testing cosmic isotropy with galaxies position angles distribution

TL;DR

This study analyzes the distribution of galaxy position angles from a large catalog to investigate potential cosmic anisotropy, finding non-random orientations that suggest possible large-scale directional effects.

Contribution

It provides a comprehensive statistical analysis of galaxy orientations, revealing non-random patterns that could indicate cosmic anisotropy or local observational biases.

Findings

Galaxies' planes are not randomly oriented in the sky.

Strong statistical evidence against isotropic distribution.

Potential implications for understanding large-scale cosmic structure.

Abstract

We analyse the distribution of position angles of 1 million galaxies from the Hyperleda catalogue, a sample that presents the galaxies coordinates in the celestial sphere, information that allows us to look for a possible privileged direction. Our analysis involves different tests and statistical methods, from which it is possible to infer with high probability ($p$-value extremely low) that the galactic planes are not randomly oriented in the sky. Whether this is an evidence of a cosmological anisotropy or an observational bias due to local effects is something deserving further studies.