  A simple yet systematic new algorithm to investigate the global structure of
Kerr-Newman spacetime is suggested. Namely, the global structure of
\theta=const. timelike submanifolds of Kerr-Newman metric are studied by
introducing a new time coordinate slightly different from the usual
Boyer-Lindquist time coordinate. In addition, it is demonstrated that the
possible causality violation thus far regarded to occur near the ring
singularity via the development of closed timelike curves there is not really
an unavoidable pathology which has plagued the Kerr-Newman solution but simply
a gauge (coordinate) artifact as it disappears upon transforming from
Boyer-Lindquist to the new time coordinate. This last point appears to lend
support to the fact that, indeed, the Kerr-Newman spacetime is a legitimate
solution to represent the interior as well as the exterior regions of a
rotating, charged black hole spacetime.

General Relativity and Quantum Cosmology;Astrophysics;High Energy Physics - Theory