Voids in cosmological simulations over cosmic time

Understand

We study evolution of voids in cosmological simulations using a new method for tracing voids over cosmic time.

• The method is based on tracking watershed basins (contiguous regions around density minima) of well developed voids at low redshift, on a regular grid of density field.
• It enables us to construct a robust and continuous mapping between voids at different redshifts, from initial conditions to the present time.
• We discuss how the new approach eliminates strong spurious effects of numerical origin when voids evolution is traced by matching voids between successive snapshots (by analogy to halo merger trees).