V S Manko and E Ruiz 2004 Class. Quantum Grav. 21 5849 doi:10.1088/0264-9381/21/24/010
V S Manko1 and E Ruiz2
Show affiliationsThe problem of comparison of the stationary axisymmetric vacuum solutions obtained within the framework of exact and approximate approaches for the description of the same general relativistic systems is considered. We suggest two ways of carrying out such comparison: (i) through the calculation of the Ernst complex potential associated with the approximate solution whose form on the symmetry axis is subsequently used for the identification of the exact solution possessing the same multipole structure, and (ii) the generation of approximate solutions from exact ones by expanding the latter in series of powers of small parameters. The central result of our paper is the derivation of the correct approximate analogues of the double-Kerr solution possessing the physically meaningful equilibrium configurations. We also show that the interpretation of an approximate solution originally attributed to it on the basis of some general physical suppositions may not coincide with its true nature established with the aid of a more accurate technique.
83C25 Approximation procedures, weak fields
83C05 Einstein's equations (general structure, canonical formalism, Cauchy problems)
Issue 24 (21 December 2004)
Received 4 May 2004, in final form 27 October 2004
Published 25 November 2004
V S Manko and E Ruiz 2004 Class. Quantum Grav. 21 5849
M. Schüssler and A. Vögler 2006 ApJ 641 L73
Shun Watanabe et al 2006 J. Phys. A: Math. Gen. 39 4273
Eric F. Bell et al. 2004 ApJ 608 752
Marco Brambilla 2002 Plasma Phys. Control. Fusion 44 2423
Geoffrey V. Bicknell et al. 1997 ApJ 485 112
U. Feldman et al. 1997 ApJS 113 195
Song Ge et al 2009 Phys. Med. Biol. 54 N177
R J Angel et al 2001 J. Phys.: Condens. Matter 13 5353
G. Á. Bakos et al. 2007 ApJ 670 826