Plotted disk surface density of a hydrodynamic simulation (Section 3.4) with a 5M_J companion on a circular orbit. The disk has a 7.5% disk aspect ratio and a 10⁻⁴ α viscosity. This snapshot is of the 250th orbit. The color contour of the plot is normalized to the initial disk density at the planet’s semimajor axis to be in code units of 1, where the warmer the color, the higher the disk density. In the snapshot, the planet was able to carve a gap and induce a vortex to develop.