2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/154005We propose an experimental scheme which allows to realize approximate time reversal of matter waves for ultracold atoms in the regime of quantum chaos. We show that a significant fraction of the atoms return back to their original state, being at the same time cooled down by several orders of magnitude. We give a theoretical description of this effect supported by extensive numerical simulations. The proposed scheme can be implemented with existing experimental setups.revtex 4 pages, 5 figs, research at http://www.quantware.ups-tlse.fr/, new data and modifications addedStatistical MechanicsChaotic DynamicsQuantum Physicstext