The darkness that shaped the void: dark energy and cosmic voids
Article first published online: 18 SEP 2012
© 2012 The Authors Monthly Notices of the Royal Astronomical Society © 2012 RAS
Monthly Notices of the Royal Astronomical Society
Volume 426, Issue 1, pages 440–461, 11 October 2012
How to Cite
Bos, E. G. P., van de Weygaert, R., Dolag, K. and Pettorino, V. (2012), The darkness that shaped the void: dark energy and cosmic voids. Monthly Notices of the Royal Astronomical Society, 426: 440–461. doi: 10.1111/j.1365-2966.2012.21478.x
- Issue published online: 11 SEP 2012
- Article first published online: 18 SEP 2012
- Manuscript Accepted: 8 JUN 2012
- Manuscript Received: 8 JUN 2012
- NOVA. Grant Number: 10.1.3.07
- DFG Priority Programme
- DFG Cluster of Excellence ‘Origin and Structure of the Universe’
- Marie Curie Intra-European Fellowship
- methods: data analysis;
- methods: numerical;
- cosmology: theory;
- dark energy;
- large-scale structure of Universe
We assess the sensitivity of void shapes to the nature of dark energy that was pointed out in recent studies and also investigate whether or not void shapes are useable as an observational probe in galaxy redshift surveys. Our focus is on the evolution of the mean void ellipticity and its underlying physical cause.
To this end, we analyse the morphological properties of voids in five sets of cosmological N-body simulations, each with a different nature of dark energy. To address the question of whether galaxy redshift surveys yield sufficiently accurate void morphologies, voids in the dark matter distribution are compared to those in the halo population. Voids are identified using the parameter-free Watershed Void Finder. The effect of redshift distortions is investigated as well.
The main conclusions of this study are as follows: (i) the statistically significant sensitivity of voids in the dark matter distribution is confirmed; (ii) the level of clustering as measured by σ8(z) is identified as the main cause of differences in the mean void shape 〈ε〉; and (iii) in the halo and/or galaxy distribution, it is practically unfeasible to distinguish at a statistically significant level between the various cosmologies due to the sparsity and spatial bias of the sample.