2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/186738We study the existence of closed trajectories of a particle model on null curves in anti-de Sitter 3-space defined by a functional which is linear in the curvature of the particle path. Explicit expressions for the trajectories are found and the existence of infinitely many closed trajectories is proved.12 pages, 1 figureDifferential GeometryMathematical Physics58E10; 49F05Closed trajectories of a particle model on null curves in anti-de Sitter 3-spacetext