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arXiv · 1404.1949

Newman-Janis Algorithm Revisited

O. Brauer·H. A. Camargo·M. Socolovsky
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Abstract

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' running from -\infty to +\infty, thus introducing in a natural way the region -\infty < r' < 0 in the above spacetimes. Using Boyer-Lindquist and ellipsoidal coordinates, we discuss some geometrical aspects of the positive and negative regions of r', like horizons, ergosurfaces, and foliation structures.

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O. Brauer, H. A. Camargo, M. Socolovsky. 2014-04-07. Newman-Janis Algorithm Revisited. https://doi.org/10.1007/s10773-014-2225-3

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