2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/67273We show that the solutions to the non-stationary Navier-Stokes equations in $R^d$, $d=2,3$ which are left invariant under the action of discrete subgroups of the orthogonal group $O(d)$ decay much faster as $|x|\to\infty$ or $ t \to\infty$ than in the generic case and we compute, for each subgroup, the precise decay rates in space-time of the velocity field.Analysis of PDEs35Q30; 35B40text