2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/33623Using a complex representation of the Debney-Kerr-Schild (DKS) solutions and the Kerr theorem we give a method to construct boosted Kerr geometries. In the ultrarelativistic case this method yelds twisting solutions having, contrary to the known pp-wave limiting solutions, a non-zero value of the total angular momentum. The solutions show that twist plays a crucial role in removing singularity and smoothing shock wave in the ultrarelativistic limit. Two different physical situations are discussed.4 pages, Latex, talk given at the session GT4 of the MG9 Meeting ( Rome, 2-9 July, 2000), submitted to the Proceedings of MG9General Relativity and Quantum CosmologyHigh Energy Physics - Phenomenologytext