Abstract
We study an evolution equation that is the gradient flow in the 2-Wasserstein metric of a non-convex functional for densities in R-d with d >= 3. Like the Patlack- Keller-Segel system on R-2, this evolution equation features a competition between the dispersive effects of diffusion, and the accretive effects of a concentrating drift. We determine a parameter range in which the diffusion dominates, and all mass leaves any fixed compact subset of R-d at an explicit polynomial rate. (C) 2021 Elsevier Ltd. All rights reserved.