Zhao, Q. -LZhang, P. -MElbistan, M.Horvathy, P. A.2026-04-042026-04-0420260219-88781793-6977https://doi.org/10.1142/S0219887825400195https://hdl.handle.net/11411/10616Ehlers and Kundt [J. Ehlers and W. Kundt, Exact solutions of the gravitational field equations, in Gravitation: An Introduction to Current Research, ed. L. Witten (Wiley, New York, 1962)] argued in favor of the velocity effect: particles initially at rest hit by a burst of gravitational waves should fly apart with constant velocity after the wave has passed. Zel'dovich and Polnarev [Y. B. Zel'dovich and A. G. Polnarev, Radiation of gravitational waves by a cluster of superdense stars, Astron. Zh. 51 (1974) 30, [Sov. Astron. 18 (1974) 17]] suggested instead that waves generated by flyby would merely displace the particles, as illustrated here by further examples.eninfo:eu-repo/semantics/openAccessPlane Gravitational WavesMemory EffectDisplacement EffectArticle2-s2.0-8521764187310.1142/S021988782540019510.1142/S02198878254001956Q223Q1WOS:001420070700001