How to Build a Catalogue of Linearly-Evolving Cosmic Voids

Abstract

Cosmic voids provide a powerful probe of the origin and evolution of structures in the Universe because their dynamics can remain near-linear to the present day. As a result they have the potential to connect large scale structure at late times to early-Universe physics. Existing "watershed"-based algorithms, however, define voids in terms of their morphological properties at low redshift. The degree to which the resulting regions exhibit linear dynamics is consequently uncertain, and there is no direct connection to their evolution from the initial density field. A recent void definition addresses these issues by considering "anti-halos". This approach consists of inverting the initial conditions of an $N$-body simulation to swap overdensities and underdensities. After evolving the pair of initial conditions, anti-halos are defined by the particles within the inverted simulation that are inside halos in the original (uninverted) simulation. In this work, we quantify the degree of non-linearity of both anti-halos and watershed voids using the Zel'dovich approximation. We find that non-linearities are introduced by voids with radii less than $5\mathrm{Mpc}{h}^{-1}$, and that both anti-halos and watershed voids can be made into highly linear sets by removing these voids.

8 pages, 5 figures. Changed to match version accepted by MNRAS (accepted 17/11/2020), minor clarifications added and no changes to the conclusions

References in corpus (8)

• ZOBOV: a parameter-free void-finding algorithm
• Dark Energy Survey Year 1 Results: Multi-Probe Methodology and Simulated Likelihood Analyses
• A measurement of the Alcock-Paczynski effect using cosmic voids in the SDSS
• Void Ellipticity Distribution as a Probe of Cosmology
• Bayesian analysis of the dynamic cosmic web in the SDSS galaxy survey
• Self-similarity and universality of void density profiles in simulation and SDSS data
• Dark matter voids in the SDSS galaxy survey
• Tracing the gravitational potential using cosmic voids

Cited by in corpus (15)

• Euclid: Forecasts from the void-lensing cross-correlation
• Why Cosmic Voids Matter: Nonlinear Structure & Linear Dynamics
• The universal multiplicity function: counting halos and voids
• EDGE: The emergence of dwarf galaxy scaling relations from cosmological radiation-hydrodynamics simulations
• The clustering of critical points in the evolving cosmic web
• Identification of Cosmic Voids as Massive Cluster Counterparts
• Catalogues of voids as antihalos in the local Universe
• Machine-learning cosmology from void properties
• Cosmology from one galaxy in a void?
• First investigation of void statistics in numerical relativity simulations
• Unveiling the Universe with Emerging Cosmological Probes
• Cosmic voids and induced hyperbolicity
• Cosmological Inference with Cosmic Voids and Neural Network Emulators
• Cluster-counterpart Voids: Void Identification from Galaxy Density Field
• An Anti-halo Void Catalogue of the Local Super-Volume