Time evolution of deviations in the midplane density ρ_mid with respect to its azimuthal average, showing the development of over- and under-dense areas near the inner radial boundary edge. The time shown on each panel refers to the time elapsed since the disk has been expanded to 3D (see Fig. 1), and the planet grows between panels e–g. The nonaxisymmetric features grow over time in panels a–e, but are dampened within a few orbits after the planet is introduced in the domain (panelf). Panel h shows that these features no longer grow in the presence of the embedded planet. Vertical dotted lines mark the end of the wave-damping zone.