Trajectories of test particles as injected from the mass center (example curves starting at R = 0). The particles are initially given different velocities and then allowed to travel for a given time T₀ (=13.7 Ga here). The end points of the curves show the locations at the time T₀. The curves marked “ΛCDM” and “no local DE” are the loci of the various particles at the time T₀ for the standard model (with DE on all scales) and for the Swiss Cheese model (no DE on local scales), respectively. The vertical line shows the zero-gravity distance. We note the minimum velocity at R = R_ZG for each ΛCDM model trajectory. Here the central mass is 2 × 10¹² M_⊙.