“Cosmic Voids in the Next Generation of Galaxy Surveys” workshop, Ohio, USA, August 18-20

Abstract:

ORIGAMI identifies halos, filaments, walls, and voids in simulations by finding folds in phase-space: the morphology of each particle is determined by the number of orthogonal axes along which it has undergone shell-crossing, giving a dynamical, parameter-free definition of structures and their boundaries. It turns out that instead of voids being completely surrounded by regions of shell-crossing (filaments, walls, and halos), the single-stream regions percolate, filling the simulation volume. Since ORIGAMI introduces no smoothing scale, the mass and volume fractions of void particles depend on simulation resolution. I will show how this affects the percolation of both single-stream voids and multi-stream regions.