2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/23571Here we study the instability of the vortex motion caused by vortex velocity non-monotonous dependence of the friction force in the presence of a gyro-force. We demonstrate that even a weak gyro-force renders the condition for onset of instability more strict than for a vortex not subject to gyro-forces: either the friction force must exceed a threshold, or its non-monotonic velocity dependence must be a rather steep function.5 pages, submitted to EPLStrongly Correlated Electronstext