Voids in VIPERS

Cosmic voids, the largest component by volume of the cosmic web, are almost completely  empty regions of space, containing very few galaxies and very low densities of dark matter.

W1_voids1 (1)
By studying them and 
by studying the few galaxies which inhabit them we can learn about the nature of structure formation, and design experiments to test dark energy. We identified over two hundred of these voids in the VIPERS survey which are presented in a paper now available online http://arxiv.org/abs/1407.2969. The average properties of these voids, such as their size distribution and density profiles are in good agreement with what we can measure on mock catalogues developed from simulations. This shows that there is no major tension between our data and the standard Lambda CDM model of the Universe.

W1_spheres1 (1)