Twisting Lightlike Solutions of the Kerr-Schild Class

Abstract

Using 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 MG9