Spinning BTZ black hole versus Kerr black hole: A closer look

By applying Newman's algorithm, the AdS(3) rotating black hole solution is "derived" from the nonrotating black hole solution of Banados. Teitelboim, and Zanelli (BTZ). The rotating BTZ solution derived in this fashion is given in "Boyer-Lindquist-type" coordinates whereas the form of the solution originally given by BTZ is given in kind of ''unfamiliar" coordinates which are related to each other by a transformation of time coordinate alone. The relative physical meaning between these two time coordinates is carefully studied. Since the Kerr-type and Boyer-Lindquist-type coordinates for rotating BTZ solution are newly found via Newman's algorithm, the transformation to Kerr-Schild-type coordinates is looked for. Indeed, such a transformation is found to exist. In these Kerr-Schild-type coordinates, a truly maximal extension of its global structure by analytically continuing to an ''antigravity universe" region is carried out. [S0556-2821(99)02504-7].