2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/22804We have reviewed recent developments of the theory of the impact for macroscopic elastic materials. This review includes (i) standard theories for the normal impact and the oblique impact, (ii) some typical approaches to simulate impact problems, (iii) and an example of our simulation to clarify the mechanism of anomalous restitution coefficient in an oblique impact in which the restitution coefficient exceeds unity.23 pages, 8 figures, to be published on nonequilibrium statistical physics in 'Phase Transitions'. Phase Transitions, to be publishedStatistical MechanicsSoft Condensed Mattertext