Large-Scale Velocity Dispersion and the Cosmic Web

Understand

Gravitational collapse in cosmological context produces an intricate cosmic web of voids, walls, filaments and nodes.

• The anisotropic nature of collisionless collapse leads to the emergence of an anisotropic velocity dispersion, or stress, that absorbs most of the kinetic energy after shell-crossing.
• In this paper, we measure this large-scale velocity dispersion tensor $\sigma^2_{ij}$ in $N$-body simulations using the phase-space interpolation technique.
• We study the environmental dependence of the amplitude and anisotropy of the velocity dispersion tensor field, and measure its spatial correlation and alignment.