  Galaxies form from the accretion of cosmological infall of gas. In the high
redshift Universe, most of this gas infall is expected to be dominated by cold
filamentary flows which connect deep down inside halos, and, hence, to the
vicinity of galaxies. Such cold flows are important since they dominate the
mass and angular momentum acquisition that can make up rotationally-supported
disks at high-redshifts. We study the angular momentum acquisition of gas into
galaxies, and in particular, the torques acting on the accretion flows, using
hydrodynamical cosmological simulations of high-resolution zoomed-in halos of a
few $10^{11}\,\rm M_\odot$ at $z=2$. Torques can be separated into those of
gravitational origin, and hydrodynamical ones driven by pressure gradients. We
find that coherent gravitational torques dominate over pressure torques in the
cold phase, and are hence responsible for the spin-down and realignment of this
gas. Pressure torques display small-scale fluctuations of significant
amplitude, but with very little coherence on the relevant galaxy or halo-scale
that would otherwise allow them to effectively re-orientate the gas flows. Dark
matter torques dominate gravitational torques outside the galaxy, while within
the galaxy, the baryonic component dominates. The circum-galactic medium
emerges as the transition region for angular momentum re-orientation of the
cold component towards the central galaxy's mid-plane.
