Newman-Janis Algorithm Revisited

  title={Newman-Janis Algorithm Revisited},
  author={Oscar Brauer and Hugo A. Camargo and Miguel Socolovsky},
  journal={International Journal of Theoretical Physics},
The purpose of the present article is to show that the Newman-Janis and Newman et al algorithm used to derive the Kerr and Kerr-Newman metrics respectively, automatically leads to the extension of the initial non negative polar radial coordinate r to a cartesian coordinate r′$r^{\prime }$ running from −∞$-\infty $ to +∞$+\infty $, thus introducing in a natural way the region −∞<r′<0$-\infty <r^{\prime }<0$ in the above spacetimes. Using Boyer-Lindquist and ellipsoidal coordinates, we discuss… Expand

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