The Size, Shape and Orientation of Cosmological Voids in the Sloan Digital Sky Survey

TL;DR

This paper introduces a new algorithm for identifying and analyzing the size, shape, and orientation of cosmological voids in SDSS data, providing insights into large-scale structure and its evolution.

Contribution

It extends previous void-finding methods, applies them to SDSS DR5 data, and compares results with LambdaCDM mock catalogs to reveal both consistencies and discrepancies.

Findings

Identified 232 cosmological voids in SDSS DR5

Found general agreement with LambdaCDM simulations

Detected significant differences in void orientations

Abstract

We present a detailed description of our void finding algorithm which is an extension of the prescription by Hoyle and Vogeley (2002). We include a discussion of the reproducibility and robustness of the algorithm as well as the statistical significance of the detected voids. We apply our void finder to the Data Release 5 (DR5) of the Sloan Digital Sky Survey (SDSS) and identify 232 cosmological voids. A void catalog which contains the most salient properties of the detected voids is created. We present a statistical analysis of the distribution of the size, shape and orientation of our identified cosmological voids. We also investigate possible trends with redshift for 0.04 < z < 0.16. We compare our results to those from an identical analysis of a mock catalog based on the LambdaCDM model and find reasonable agreement. However, some statistically significant differences in the overall orientation of cosmological voids are present and will have to be reconciled by further refinement of the simulations.