Wahlquist-Newman solution - art. no. 064022

Based on a geometrical property which holds both for the Kerr metric and fo r the Wahlquist metric we argue that the Kerr metric is a vacuum subcase of the Wahlquist perfect-fluid solution. The Kerr-Newman metric is a physical ly preferred charged generalization of the Kerr metric. We discuss which ge ometric property makes this metric so special and claim that a charged gene ralization of the Wahlquist metric satisfying a similar property should exi st. This is the Wahlquist-Newman metric, which we present explicitly in thi s paper. This family of metrics has eight essential parameters and contains the Kerr-Newman-de Sitter and the Wahlquist metrics, as well as the whole Plebariski limit of the rotating C metric, as particular cases. We describe the basic geometric properties of the Wahlquist-Newman metric, including t he electromagnetic field and its sources, the static limit of the family an d the extension of the spacetime across the horizon.