Exact solutions of the Einstein-Maxwell equations with closed timelike curves

摘要

We examine two electrovac spacetimes, the Kerr-Newman solution and another due to Perjes, which represent single charged, rotating, magnetic objects. Both contain regions with closed timelike curves (CTC), but these regions would be covered by the sources in any physical realisation of the spacetimes, so the CTC would not be detectable. We then study a stationary solution referring to two charged, rotating, magnetic objects. In general there is a region of CTC between the objects no matter how far apart they are. In this case the region would not be covered by the sources, and CTC would be detectable in principle.